RECORD: Armstrong, Patrick. 1992. Charles Darwin's last island: Terceira, Azores, 1836. Geowest no. 27.

REVISION HISTORY: Scanned by John van Wyhe, transcribed (single key) by AEL Data, corrections by van Wyhe 9.2009. RN1

NOTE: The copy scanned was lent by Gordon Chancellor. Reproduced with the kind permission of Patrick Armstrong.

Books by the same author:

Charles Darwin in Western Australia: A young scientist's perception of an environment. Nedlands: University of Western Australia Press, 1985. Text

Under the blue vault of heaven: A study of Charles Darwin's sojourn in the Cocos (Keeling) Islands. Nedlands: Indian Ocean Centre for Peace Studies, 1991. Text

Darwin's desolate islands: A naturalist in the Falklands, 1833 and 1834. Chippenham: Picton Publishing, 1992. Text

The English Parson-Naturalist. Gracewing, 2000.

All Things Darwin: An Encyclopedia of Darwin's World. Greenwood: Connecticut, 2 vols., 2007.

Darwin's Luck. Continuum, 2009.


[front cover]

Charles Darwin's Last Island: Terceira,
Azores, 1836

by

Patrick Armstrong

Department of Geography
University of Western Australia

Geowest No 27
University of Western Australia, Nedlands, Western Australia, 6009
1992

[page break]

[page i]

Charles Darwin's Last Island: Terceira,
Azores, 1836

by

Patrick Armstrong

Department of Geography
University of Western Australia

Geowest No 27
University of Western Australia, Nedlands, Western Australia, 6009
1992

[page ii]

© P H Armstrong 1992

Department of Geography
University of Western Australia
Nedlands
Western Australia, 6009

ISBN 0 909678 359

[page iii]

Contents

Introduction 1
Chapter 1
Darwin's Azores experience 8
Chapter 2
Itinerary 15
Chapter 3
Geological observations 26
Chapter 4
Countryside, town and people 41
Chapter 5
Echoes of home 51
Concluding summary 55
Appendix A
Charles Darwin's accounts of the steam vents of
Furnas do Enxofre
57
Appendix B
Possible errors in the dates in Darwin's Diary 59
Notes and references 61

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Figure 1. Position of Terceira and the Azores.

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Introduction

This book has been written as a part of an extended programme of research on aspects of the Charles Darwin's work during the voyage of HMS Beagle, and its long-term significance to the great Victorian naturalist's intellectual development. While Darwin's explorations in the Galapagos Archipelago, in the eastern Pacific Ocean, have been much discussed, in both the popular and scholarly media, very much less has been written on his visits to other island groups and land masses. In a number of previous publications I have considered Darwin's work in parts of Australia, New Zealand, the Cocos (Keeling) Islands, Mauritius, the Cape of Good Hope and the Falklands, in an attempt to throw light on the way in which Darwin conducted his work in the field, recorded his observations, and to some extent at least, thought about, his experiences.1 I have tried to show that there was much more to the Beagle voyage than just the Galapagos that have captured so much of the popular imagination.

These earlier studies examined Darwin's work on islands in the Pacific, Indian and South Atlantic Oceans, and the continental land masses of Australia and Africa. These localities have provided examples of Darwin's methods of work from several different parts of the voyage (early 1833 mid-1836), and the studies have enabled me to accompany him onto coral reefs, to the bleak Falklands, to the forests, mountains and shrublands of continental environments, but not to a true volcanic island. An examination of a volcanic islet, one on which Darwin had actually seen residual thermal activity, and one that he had visited at the very end of the voyage, as the Beagle sailed northwards through the North Atlantic, seemed a way of filling a number of gaps.

My approach has been to examine as many as possible of the written sources, published and manuscript, that bear upon Darwin's relationship with a particular locality, and then, almost literally, "take the archives to the field" by examining the actual sites that Darwin visited over the years of his epoque-making voyage, 1831-1836. Copies or photocopies of Darwin's notes and other writings are used in an attempt to reconstruct the routes taken during his journeyings, to establish a detailed chronology, to locate the sites that he describes in his notes and from which he collected specimens, and, where appropriate, to compare his comments with the views of modern scientists. In this way I believe it is possible for a modern enquirer to "get into the mind" of his subject to a greater extent than through work in the archive room or library alone. Further, in adopting this approach, it is possible to convey

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something of a "sense of place" to the reader, and to reflect Darwin's experience of, and attitude to, particular environments.

Darwin said nothing about his visit to Terceira in his best-remembered work, the book that has become known as The Voyage of the Beagle, and so that researcher has to refer to other sources. These include his personal diary or journal (referred to here as the Diary, and first published in 1933 (by Cambridge University Press) as Charles Darwin's Diary of the Voyage of HMS Beagle, edited by his granddaughter, Nora Barlow)2 and his Geological Diary, now preserved with many of his other papers in the Darwin Archive in Cambridge University Library.3 Information on how Darwin approached his work, and his anticipation of the Azores visit is included in a letter he wrote to his sister Caroline, from Brazil a few weeks before the visit.4 An exact chronology of the Beagle's movements in Azores waters, and details of the weather during the visit can be gained from the Log of the ship (in the Public Record Office, Kew, at ADM 51/3055). The information in the log is quite important in the case of the stay at Terceira, as there are grounds for believing that some of the dates given in Darwin's Diary are out by a day or so. This matter is discussed in Appendix B.

For some ports of call, the rather basic diary (now in the Mitchell Library, Sydney, NSW)5 kept by Darwin's servant, Syms Covington, provides useful corroboration, and indeed occasional detail that cannot be garnered from other sources. Although Darwin, perhaps because of some perceived social divide, seldom refers to Covington in his letters or diaries, it seems that his servant sometimes accompanied Darwin on his explorations. In the case of the Terceira visit we can be fairly sure that Syms Covington did not accompany his master. Covington's diary makes no mention whatever of any of the localities included in Darwin's itinerary, and he notes that "all parts of the 1d seen from the ship" were cultivated. One of his few other comments of substance is: "Fruit & vegetables &c &c are very cheap". My interpretation of this is that Syms did not stray far from the Beagle and perhaps the traders' stalls of the little part of Angra (Figure 2).

Although Charles Darwin did not utilize his Azorean experience in The Voyage of the Beagle, he did in some of his later writings, particularly volume 2 of The Geology of the Voyage of the Beagle, on Volcanic Islands, 6 and thus a number of quotations from this work are included here. Indeed from this volume it can be seen that the Terceira sojourn had a small but significant part to play in the development of some of his ideas.

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For some parts of the voyage, the enquirer has Captain Robert FitzRoy's comments; the difficult but brilliant Commander of the Beagle wrote part 2 of The Narrative of the Surveying Voyages of His Majesty's ships Adventure and Beagle,7 which in some instances gives a complementary view to Darwin's book (originally part 3 of the same work). But FitzRoy's Narrative says nothing about the stay at Terceira; however a statistical appendix to FitzRoy's account gives slight clues to the nature of some of the navigational measurements made there.

The Azores archipelago is made up of nine emergent volcanic islands, on a shallow oceanic platform astride the mid-Atlantic Ridge, between about Lat 37° and 40°N. They are aligned in a broadly WNW to ESE direction between Long 24° and 31°W (Figure 1). They are primarily of alkali basalts, although the detailed geochemistry and petrology of the lavas are quite varied.8 The islands have been active seismically throughout the historic period, the most recent earthquake being one in 1980 that damaged the city of Angra do Heroismo9 and nearby settlements. The latest eruption was in 1957-58 on Faial.

Many of the islands are very elongate in outline, including São Miguel, which Darwin observed from the ship while the Beagle waited briefly offshore as a small boat was sent ashore, but upon which he did not land. The archipelago is isolated, being situated approximately 1450km (900 miles) due west of the city of Lisbon in Portugal. Politically the islands form a part of that country. Although they were apparently known to Arab geographers in the twelfth century, they were not rediscovered until about 1427 by Portuguese sailors. Settlement (from Portugal) began around 1450.

Terceira is one of five islands constituting the Central Azores group (the others are Graciosa, São Jorge, Faial and Pico). It is 29km (18 miles) from east to west, a maximum of 17.5km (11 miles) north to south. The area is given as 381.96sq km. The uplands are associated with four major volcanic centres, the highest point being at 1021m (3350 feet) in the Serra do Santa Barbara, just south of the Caldeira (ie crater) do Santa Barbara, in the west of the island. A large number of smaller volcanic cones, in varying states of dissection, pimple the landscape of much of the island (Figure 3); only in the extreme north-east, north of Vila da Praia da Vitória10 (usually just Praia; Praya in Darwin's writing) is the land flat. The climate is equable the average daily temperatures are 17°C in January, 25°C in July but rainfall totals and humidity levels are quite high. Fragments of the original vegetation of laurel forest with giant heathers survive but there has been substantial admixture with exotic species of plants,11 and a high proportion of the land has been

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cleared. The last couple of decades have been the establishment of plantations, including some of Australian eucalypts. The population is about 60,000 of whom about 20,000 live in Angra do Heroismo and 7,000 in Praia; the remainder live in about 32 villages, that, necklace-like encircle the island. The usually white-painted houses originally clustered round the parish churches, but as the population increased, settlements expanded into the countryside, so that a sprinkling of white cottages now dots much of the lower ground of the island. The combination of the light-coloured cottages, the rectilinear pattern of drystone walls (Figure 5), and the brilliant green pastureland gives the landscape something of an Irish flavour. Portugal's membership of the European Community, and a small tourist industry have contributed to a quiet rural prosperity, but the reduction in the employment at the United States military base has brought the cool breeze of economic hardship and uncertainty to these otherwise fortunate isles.

My own visit to Terceira took place in late April and early May, 1992 (ie about five months earlier in the year than Darwin's visit in September 1836). Some of the equipment I had with me would have been recognisable to Darwin. Like him I carried a geological hammer and magnetic compass, and of course a note-book and pencils. I had the advantage over him of a light pair of 10 x 25 binoculars, and two 35mm cameras a Praktica SLR, and a lighter Pentax. Whereas the nineteenth century traveller had little in the way of maps, today a 1:50,000 topographic map of the island is available, produced by the Intituto Geográphico e Cadastral (Sheet M7811), albeit an edition first published in 1965.

This work could have been completed without the support of the Geography Department of the University of Western Australia, and the University's 75th Anniversary Fund. The rock hand-specimens were photographed by the University Media Services Section (the other photos are my own); Guy Foster drew the maps. Dave Murray and Viv Forbes read a draft of the text, and, each from his own point of view, made many useful suggestions. To the friendly Açorianos with whom I came into contact I say "Mulito obrigado". My wife Moyra allowed me to run away on "yet another Darwin hunt" and in doing so to enjoy a warm, sunny, northern hemisphere spring while leaving her in a rainy southern autumn. Despite this she was smiling at Perth International Airport at 2.00 am to meet me: Thank you, Darling!

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Figure 2. The port of Angra do Heroism, Terceira, from the slope of Monte Brasil.

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Figures 3 and 4. Volcanic cones, Terceira

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Figure 5. Pattern of fields and walls, north-eastern Terceira. From an aerial photograph.

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Chapter 1

Darwin's Azores Experience

Darwin seems to have been looking forward to his visit to the Azores. In his hastily scribbled last letter from the Beagle to his family in Shrewsbury, from Bahia, Brazil, and dated 4 August 1836 he wrote:

We go from here to the C. de Verds, that is if the winds or the Equatorial calms will allow us.- I have some faint hopes, that a steady foul wind might induce the Captain to proceed direct to the Azores.- For which most untoward event I heartily pray.1

This slightly obscure passage I interpret to mean that he hoped that the Captain would go directly to the Azores, instead of deflecting to the east to re-visit the Cape Verde Islands. (In the event he did visit the Cape Verdes.) Thus Darwin quite keenly anticipated the Azores visit, at least partly because it would be the last port of call before the return to England, and arrival in the archipelago would mean that the difficult equatorial regions had been left behind for the last time, and the final run for England would then be at hand. The letter (addressed to his sister Susan) is full of Charles' hankerings for home and family, as well as passages such as: "I loathe, I abhor the sea, & all ships which sail on it"! Darwin had by then lived for four and a half years on HMS Beagle and was fed up with every aspect of the sailor's lifestyle.

But there may be slightly more to Darwin's anticipation of the Azores as a symbol of the start of the final stage of the voyage. Yet another passage in this "last letter" runs:

The desert Volcanic rocks & wild sea of Ascension, As soon as I knew there was news from home, suddenly wore a pleasing aspect; & I set to work, with a good will at my old work of Geology. You would be surprised to know, how entirely, the pleasure of arriving at a new place depends on letters.

Possibly also Darwin anticipated the Azores also as a possible pick-up point for letters, as well as a further locale for his "old work of Geology". He had certainly put the four-day visit to Ascension to good use; the notes he made there formed the basis for an entire chapter in Volcanic Islands.

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But despite the modest eagerness of his anticipation, Darwin passes over his brief sojourn in the Azores in his Voyage of the Beagle with the bald statement that after a stay in the Cape Verde archipelago: "[W]e proceeded to the Azores, where we staid six days." When one compares this with the detail with which Darwin described parts of South America, his few weeks in Australia, and certain other islands and archipelagoes at which the ten-gun brig converted for hydrographic work spent time, this might seem surprising. Darwin was fascinated by islands: he visited many during the circumnavigation: St Paul's Rocks, the Falklands (twice), Tierra del Fuego, Chiloe, the Galapagos, Tahiti, New Zealand, the Cocos (Keeling) group, Mauritius, Ascension, St Helena and Cape Verde (twice). His studies on islands formed the basis of two volumes of The Geology of the Voyage of the Beagle, those on Coral Reefs and Volcanic Islands. The Galapagos, he himself later felt, played a particularly important part in the development of his evolutionary ideas, and literally dozens of his later articles, and not a few of his books, included material collected during his "island days".

Although he found a number of things of great interest during his visit to Terceira (the only island of the Azores on which he landed), he displayed a certain lack of enthusiasm for the place. Darwin had a very definite "sense of place", and sometimes reacted strongly either positively or negatively to many of the environments he experienced. He did not like Australia, New Zealand or the Falklands; he did like Cocos and Mauritius despite finding things of which he disapproved at both of the latter. Let us briefly consider the way in which Darwin worked and perceived the world about him in an attempt to explain he reaction to what he admits was in many ways a picturesque and rather charming landscape.

Any individual sees the world to some extent through the lens provided by his or her upbringing, education and experience. Darwin was no exception. He had been brought up in a well-to-do doctor's family in Shrewsbury. His domineering father, Robert Darwin, adhered strongly to the Whig tradition. The family was liberal, even free-thinking, in matters of religion, but after abandoning thoughts of a medical career after two years at medical school in Edinburgh (which he hated), he had studied a general arts course at Cambridge with a view to taking Holy Orders in the Church of England. The time in Cambridge was particularly important as it brought him into contact with the Reverend Professor John Stevens Henslow, Professor of Botany (and formerly of Mineralogy), who ha developed the young Darwin's interest in natural history, and who had been instrumental in arranging the Beagle appointment. But Edinburgh no doubt had an influence too: he may have got something of his fascination

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with people and eye for detail from his days at medical school (and also perhaps from occasionally visiting patients with is doctor father). And throughout his travels the young naturalist displayed a dislike of humbug, a scorn for those who abused people of other races in their care, and a respect for the human dignity in all manner of persons of which his Whiggish family would have approved.

Observing and collecting

Darwin was a brilliant observer, whether describing a whole landscape, or the minutiae of a rock's petrology. Here is part of the first page of his geological notes:

1836 Terceira Azores 957 (1)

The island of Terceira appears to consist of an elevated central part which slopes down on all sides to the sea.- Both on the flanks and on the summit there are scattered numerous volcanic summits. The streams of lava, which have proceeded from these can in some cases be traced. And the surface, especially in parts of the elevated central land, in covered by hummocks & irregular depressions. These more modern streams, when I saw them [chiefly] consist of a blackish lava.- Specimens (3212, 13, 14) show their nature.- Besides these streams, there are irregular ridges & large hills chiefly composed of true white or pale grey trachyte full on broken crystals of glassy feldspar [sic], brown line & minute black points precisely similar to the trachyte of Ascension. (DAR 38.2/957)

And here his account of the costume of some of the country people of Terceira:

The men and boys are all dressed in a plain jacket & trowsers [sic], without shoes or stockings; their heads are barely covered by a little blue cloth cap with two ears & a border of red; this they lift in the most courteous manner to each passing stranger.2

But as well as the fine detail, Darwin saw the the whole picture, and the way in which a human community impacted on a landscape. See, for example his economical account of São Miguel, quoted on page 22, or his description of the settled landscape north of Angra through which he passed on his first full-day excursion on Terceira, page 17, Chapter 2.

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One way in which his pattern of working was significantly different from that adopted at other ports of call is the paucity of his collection of specimens. At many other locales visited during the voyage he collected dozens or even hundreds of specimens rocks, fossils, plants, shells, insects and other invertebrates, fish, birds, mammals, reptiles and amphibians. At Terceira he collected only about half a dozen rock specimens the four-digit numbers in the quotation above from the geological notes refer to numbers on the specimens, keyed to note-book entries elsewhere. He does not seem to have collected any insect specimens after his visit to Bahia in Brazil in early July, and he apparently collected no plants during this part of the voyage. Certainly by this stage of the journey his cases of specimens must have been very full, and some of the things he might have collected would perhaps represent duplicates of what he had obtained elsewhere. Also, many of the plants and birds of Terceira were familiar species from Britain. But maybe he was just impatient to be home, and this impatience was aggravated by the very familiarity of some aspects of the environment. This last point will be returned to later.

I have emphasised elsewhere the importance of Darwin's comparative turn of mind. The comparative approach that was so important in his later work on evolution was already well-developed in his days aboard the Beagle. He was constantly, in his notes, comparing his own observations made in one locality with those he had made elsewhere. He also compared his findings with those of others: many times he makes reference in his notes to the descriptions given by some earlier explorer, naturalist or traveller, for aboard the Beagle was a library of hundreds of volumes, some general reference works such as Encyclopaedia Britannica but also including many accounts of earlier voyages.3 Sometimes his comparisons serve simply as an aide memoir, to enable himself at a later time, or another reader, to picture a particular instance. But often the comparative method has explanatory value: as Darwin himself put it: "the habit of comparison leads to generalisation". Here is his diary account of the way in which ruts were cut into the lava:

I noticed in several places, from the long traffic of bullock waggons [sic], that the solid lava which formed in parts the road, was worn into ruts of the depth of twelve inches. This circumstance has been noticed with surprise in the ancient pavement of Pompeii, as not occurring in any of the present towns of Italy. At this place the wheels have a tire surmounted by singularly large knobs; perhaps the old Roman wheels were thus furnished.

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Note the "perhaps"; Charles Darwin was cautions in his writing when he was not sure, he said so!

He compared the way of life of the people of Terceira with that of the inhabitants of Chiloe, the island off the west coast of South America that he had visited over a year before, as well as with "the Portuguese of Brazil". He also compared the landscape of Terceira with that of São Miguel (see page 22).

His geological notes on Terceira are also full of comparisons:

The degree of activity about equal to the Galapagos, & Cape Verd & Canary. With respect to age, of each crater degradation.-

… lavas of a smooth texture, of a blackish colour with crystals of glassy felspar [sic] similar to some on James Isd.-

Both these islands [ie Terceira and São Miguel] in their general form, number of craters, few scattered mounds, Lithological nature of the rocks … degree of activity, general dimensions appear very closely to agree with the Galapagos Archipelago.-

No true Trachyte at Galapagos.

Thus in his eye for detail, his interest in the whole environment rocks, landforms, organisms, and the human community in addition to his cautious scientific approach, and his "habit of comparison" the young naturalist's approach to his work in the Azores was very similar to that which he had displayed at other islands and continents. But in the poverty of his collecting, and in the odd remark that he lets slip, he displays an eagerness to be on his way and an impatience for home, family and things familiar.

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Figure 6. The "crateriform" Monte Brasil from the north, inland from Angra.

Figure 7. Terceira, Azores, showing location of places mentioned in text and Darwin's routes.

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Figure 8. Angra do Heroismo, Terceira, Azores, showing the grid-like form of the Old Town, the Port, castles, fortifications and the many "fine churches".

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Chapter 2

Itinerary

In the Introduction it was explained that although the log of HMS Beagle provided an important means enabling the activities aboard the ship to be reconstructed, for a full picture to be obtained, recourse has to be made to other sources, and where possible, this archival material to be related to the actual environment. This chapter represents an attempt to build a chronology using a variety of sources, and so provide an impression of the background and circumstances under which Darwin worked.

Captain Robert FitzRoy did not often enter the noon position of His Majesty's Surveying Sloop Beagle in the log himself; the entry was usually carefully inked in by his clerk or by one of the other seamen. But the brilliant, but rather difficult commander checked the entries carefully, and regularly countersigned the completed pages with something of a flourish. It can be assumed that he carefully checked the noon readings for 18 September 1836. The Beagle was approaching her final landfall on her five-year circumnavigation of the globe, a voyage that had been outstandingly successful in many respects; he would not have wanted anything to have gone wrong at this late hour.

The entry in question read:

Distance Lat. Long. Bearing and Distance
DR Obs DR Chron
115 37.57 38.03 27.33 27.39 Angra N29E 41 miles

This can be interpreted as follows:

The vessel had traversed 115 nautical miles since noon the previous day. The position of the ship had been determined at 37° 57′N and 27° 03′W by dead reckoning (ie based on the estimated distance traversed, and course steered, since noon the day before), but 38° 03′N and 27° 39′W by instrument readings (sextant and chronometer). This placed the ship at a point from which the little harbour of Angra on the island of Terceira lay 41 nautical miles distant, on a bearing a little east of north.

The wind was from the south-east, force 2. It was fine: white clouds drifted across a vivid blue sky. At 2.00pm the sails were trimmed; the port lower studdy sail was shifted and the starboard foretopmast and

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topgallant studdy sails, together with the mainsail were set. Further adjustments were made at 3.00pm and again at 4.10pm.

By 7.50 in the evening the wind had strengthened to force 4, and shifted to S 1/2 W, although it remained fine. This wind change required the sails to be shortened, and the topsails and fore topmast staysails were double reefed, as the ship hauled to the wind on the starboard tack. Later still the wind drifted further round to the north-west, and as the Beagle entered the port tack, further adjustments were made the foresail and the the main topsail were set.

At 4.00am on Monday 19 September land could just be made out to the nor' nor' west, and as daylight grew brighter, the form of the island could be made out more clearly: the easternmost point (Ponta de S. Jorge) lay NE by N; the wind strengthened again, and the ship "made all sail to Royals".

At 6.00am the sun was rising, and as the ship tacked again, and little town of Angra could be seen beneath the island's hills some six or seven nautical miles to the NW by N. Charles Darwin was evidently on deck by an early hour of the morning, for in his diary he recorded: "In the morning we were off the East end of the island of Terceira". He observed the land carefully, noting that it was "moderately lofty & has a rounded outline with detached conical hills of volcanic origin."1

At 9.00am one of the ship's boats was lowered, and sent ahead to the town, the Beagle herself working slowly, tacking occasionally towards the tiny, exposed harbour just to the east of Monte Brasil. At noon she came to in 35 fathoms, anchoring with "Best Bower" (the largest bow anchor). As the coast shelves relatively gently to the south of the island, this must have been a good few cable's lengths out from the shore possibly between one and two kilometers.

During the afternoon, while many of the crew were employed blacking the rigging and yards, painting the ship, and mending hammocks, the ship "veered to 45 fathoms" and a third reef was taken in of the topsails.

In the evening, Darwin records, "a party went on shore". Darwin and his companions evidently spent some time looking around the streets of the attractive town of Angra, examining some of the churches, glancing up at the defensive works at the foot of Monte Brasil, and wandering along the tightly packed streets that tumbled down to the tiny harbour. He rather liked the place, but found it a little sleepy. Possibly Darwin and one or two other officers called on the British consul (FitzRoy made a point of paying courtesy calls on local dignitaries at a number of the ports that

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the Beagle visited). The young naturalist records in his diary:

The next day the Consul kindly lent me his horse & furnished me with guides to proceed to a spot in the centre of the island, which was described as an active crater.

The day's ride (Tuesday 20 September) was a quite a long one, and so he must have started fairly early. It is thus reasonable to assume that arrangements for the loan of the horse and the appointment of guides were discussed the previous evening.

Tuesday's weather was rather unsettled, overcast and showery, with quite a strong wind (force 5) from the west sou' west. While many of the crew of the Beagle continued with the maintenance of the ship and painting, Darwin set out on horseback more or less due northwards from the town. His description of the landscape is quite detailed:

Ascending in deep lanes bordered on either side by high stone walls, for the first three miles, we passed many houses & gardens. We then entered on a very irregular plain country, consisting of more recent streams of hummocky basaltic lava. The rocks are covered in some parts by a thick brushwood about three feet high, & in others by heath, fern & short pasture: a few broken down old stone walls completed the resemblance with the mountains of Wales. (Diary)

The first few lines of this account could apply today to much of the gently sloping country north of Angra, but the description does not allow the route to be identified exactly. Possibly he went through the attractive village of São Antonio. The reference to "irregular plain country" suggests that he crossed the plateau to the east of the Serra do Marido, before striking east through a low col, the route now taken by the main east-west road across the island (Route EN 5.2a), to the Furnas do Enxofre, the fumaroles that were his destination, and where he probably spent some time examining the steam-vents and collecting rock specimens (see chapter 3).

The by now seasoned young explorer observed and recorded in some detail the nature of the rocks, landforms and some of the birds that his saw. He also always took the greatest interest in the human inhabitants of the countries he visited, and he wrote: "it was pleasant to meet such a number of fine peasantry", describing their physical appearance, clothing, implements and way of life in some detail. He summarized: "I enjoyed my day's ride, although I did not see much worth seeing". Perhaps much of

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the landscape had too familiar an aspect to excite him; he had seen volcanic landforms and rocks before (in New Zealand, Ascension Island and the Galapagos for examples), and some aspects of the cultural landscape reminded him of England or Wales and yet he was still far from home.

Darwin's diary continues:

Another day I set out early in the morning to visit the town of Praya seated on the N.E. end of the island.

If this trip had been on the following day after the visit to the fumaroles, Darwin, would surely have said "On the next day" rather than "Another day", and in any case his account of the day on which Praia was visited ends with the evening departure of the Beagle from Terceira. As the captain's log shows very clearly that the ship sailed on 22 September, we can assume that it was on that day (Thursday) that Darwin visited the north-east of the island, including the town of Praia.

The only other excursion of any length on which Darwin went during the Terceira sojourn was to Monte Brasil, to the west of the town of Angra. He describes the form of this volcanic crater, and the rocks that compose it, in some detail in his geological accounts, although he says very little about this site in his diary. The site could be visited within a few hours on foot from Angra, or the aspiring geologist might even have been put down at the foot of the mountain by ship's boat, and picked up later. Indeed the Appendix of navigational and meteorological data in FitzRoy's Narrative clearly implies that observations (latitude, longitude, magnetic variation) were made from the top of Monte Brasil, and it is quite possible that Darwin accompanied the group doing this work. These measurements were often made by Lieut Sulivan, a special friend of Darwin with whom he sometimes went on geological walks. Nothing would be more natural than for the naturalist to accompany the observations party, scouting around and examining geological exposures while his shipmates set up their instruments.

My guess, therefore, is that on the overcast Wednesday 21 September, while, as the log puts it the ship lay "At single anchor in Angra Roads", he spent at least part of the day climbing Monte Brasil (he always refers to Mount Brazil in his notes), and collecting rock specimens from its flanks.

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Figure 9 (above). "… deep lanes bordered on either side by high stone walls … Figure 10 (below). "… a few broken down old stone walls completed the resemblance to the mountains of Wales."

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For 22 September, however, he records: "I set out early in the morning," and there is every indication that it was very early indeed. He notes of his ride to Praia (he uses the spelling Praya):

The distance is about fifteen miles; the road ran the greater part of the way not far from the coast.

The route Darwin followed must have been very close to that of the modern coastal road (EN 1.1a). He must have passed through the village of Feteira, and probably the pretty coastal settlement of Porto Judeu, for he wrote:

One part of the road crossed a broad stream of lava, which from its rocky and black surface, showed itself to be of comparatively recent origin; indeed the crater whence it flowed could be distinguished. The industrious inhabitants have turned this space into vineyards, but for this purpose it was necessary to clear away the loose fragments & pile them into a multitude of walls, which enclosed little patches of ground a few yards square; thus covering the country with a network of black lines.2

This still represents an accurate account of the country along the coast near Porto Judeu, where fragments of black lava have been built into walls a metre or so high, enclosing tiny parcels of land, sometimes just four or five metres square: the vivid green of the vine leaves contrasts spectacularly with the black lava (Figure 11).

Darwin may have cut inland just beyond Porto Judeu, through São Sebastiao, for the coast is steep, and in places inaccessible. The modern road (EN 1.1a) runs two or three kilometers inland from the coast, and probably the deeply rutted track that Darwin followed did the same.

He did not linger long in Praia, which he thought "a forlorn little place", although he comments briefly on a collapsed wall of a convent "now bathed by the sea". His diary continues:

I returned home by another road, which first leads along the Northern shore, & then crosses the central part of the Island. This North Eastern extremely is particularly well cultivated, & produces a large quantity of fine wheat … . We soon reached the region of clouds, which during our whole visit have hung very low & concealed the tops of the mountains. For a couple of hours we crossed the central part, which is not inhabited & bears a desolate appearance.

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Clearly the traveller set out northwards from Praia, and he must have passed very close to the site of the modern airport; perhaps his horse passed between the white cottages of the villages of Lajes and São Bras. It is just possible that from one of these villages he struck south and the traverse of the high mountainous area in the clouds refers to the narrow ridge of the Serra do Cume. But this is hardly in the "central part" of the island, and crossing this narrow but steep range of hills would hardly take two hours. Although the route is much longer, I feel Darwin must have continued along the north coast as far as Vila Nova, and then worked his way south through the main massif of mountains, following a track beside one of the north-east flowing streams west of Pico Alto (High Peak, 808m). See Figure 7. A few poor tracks traverse this area today, and as we have seen, he almost certainly had a guide. He would thus have passed not very far from the fumaroles he had visited a couple of days before. This admittedly makes a round trip of nearly 50km (some 30 miles), including stiff country and with indifferent weather; he also stopped occasionally to make observations.

To complete this trip by between 3.00 and 4.00pm (the ship "weighed and made sail" at 4.20pm according to the log, and horses had to be returned, the guides paid off, and the ship's boat to convey him to the Beagle) would have been an undertaking, but not impossible. We must indeed assume an early start (perhaps 5.00am), a good horse and competent guidance not like that of the "stupid fellow" who had attempted to guide Darwin up Mt Wellington in Tasmania, a few months before, and got them both hopelessly lost!

Certainly there is a note of tiredness and eagerness to be away in the final words of the description of the day's outing:

When we descended from the clouds to the city, I heard the good news that observations had been obtained, & that we should go to sea the same evening. The anchorage is exposed to the whole swell of the Southern ocean, & hence during the present boisterous time of year is very disagreeable and far from safe.

At 4.20pm, then, with a force 5 sou'wester billowing out the sails, HMS Beagle "made sail on the starboard tack to the topgallant sails". At 6.40pm, the vessel briefly hove to, and the ship's boat was taken up. At 7.00pm the sails filled again and a course was set for the island of São Miguel (St Michael's, as Darwin called it), Some 80 nautical miles (approximately 150km) to the south-east. The night's sailing was relatively uneventful, although the ship later that evening passed "a

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small schooner standing to the NW".

Daylight on the morning of 23 September 1836, a force 4 sou'wester still blowing behind her, saw the Beagle, as Darwin put it, "off the Western end of St Michael's", or as the log states, the island was to be seen "bearing SE to S by E". The Royals and the flying jib were set at 6.30am, but to little avail: the entry for 8.30 states that the ship was "taken aback"; the wind slackened it became just a series of "light and variable airs". At 9.00 the whale boat left the ship to put into the principal town, Ponta Delgada, to enquire for letters, the Beagle sailing slowly about to await the boat's return. There is evidence2 that the shore party briefly set up instruments near "St Braz Castle" (For São Brás), close to the port, and navigational and magnetic observations were made.

Meanwhile, aboard the Beagle, by 10.20am the breeze had strengthened, there was the odd squall about, and the ship "trimmed to a light breeze to from the SW". The morning passed slowly and at 11.00 the "Hemp cable" (presumably the major anchor rope) was got up to dry; perhaps Captain FitzRoy was looking for work to keep the men occupied while they waited. Once an Austrian brig passed them, a tiny spot of relief to the hours of tedium. Darwin wrote in his diary "a contrary wind detained us", but was keenly observing the island from a few miles offshore, comparing the landscape with that of Terceira:

The Isd of St Michael's is considerably larger & three times as populous & enjoys a much more extensive trade than Terceira … . St Michael's has much the same open, semi-green, cultivated, patchwork appearance as Terceira. The town is scattered; the houses & churches there & throughout the island are white washed & look from a distance neat & pretty. The land behind the town is less elevated than on Terceira, but yet rises considerably; it is thickly studded or rather made up of small mammiformed hills, each of which has sometime been an active volcano.3

At 4.00pm the whale boat returned "without any letters, & then getting a good offing from the land, we steered, thanks to God, a direct course for England."

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Figure 11. "The … inhabitants have turned this space into vineyards … . [I]t was necessary to clear away any loose fragments and pile them into … walls which enclose little patches of ground a few yards square." Near Porto Judeu, Terceira.

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Figure 12. "Mount Brazil [Monte Brasil] … built of thin strata of fine-grained, harsh, brown-coloured tuff."

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Figure 13 (above). Tuff from Monte Brasil. The scale is in millimeters and centimeters. Figure 14 (below). The Iléus das Cabras remnants of a volcanic cone eroded by the sea, just offshore from Angra.

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Chapter 3

Geological Observations

Charles Darwin was an extremely enthusiastic geologist. His formal training had been limited to three weeks of fieldwork in North Wales with Professor Adam Sedgwick in the summer of 1831, but in that brief excursion he had grasped enough to be able to make a major contribution to the subject on the basis of his Beagle observations. His three volume Geology of the Voyage of the Beagle probably had more impact on the scientific community than some of his early biological work. He certainly saw himself as a geologist while aboard the Beagle, collecting thousands of specimens and compiling his hundreds of pages of geological notes. During the long sail northwards from the south Atlantic in 1836 he wrote to his old friend and teacher, Professor Henslow, his "First Lord of the Admiralty", enquiring about being proposed as a member of the Geological Society of London.

Darwin's studies of the geology of Terceira are more thorough than his annotations on any other topic. He left three accounts of the geology of the island:

1. His account is his Geological Diary, hitherto unpublished. These consist of five pages of detailed, but rather crudely written annotations, including descriptions of rock specimens keyed to specimen numbers. These notes were probably written aboard the Beagle very shortly after his return from the field. They are in the Cambridge Archive at DAR 38.2/ 957-960.

2. His descriptions of particular aspects of the geology of Terceira, intermingled with his account of other aspects of the island, and his own day-to-day activities, in his Journal or general Diary. These, too, were written on board ship, not many days after his visit. Indeed it is possible that some entries in the Diary were written actually while the Beagle lay at anchor in the harbour at Angra.

3. His more considered summary of the geology of the island, which forms a part of chapter 2 of his book Volcanic Islands, volume 2 of the Geology of the Voyage. This is a good deal more polished than either the above, and is based on them. It was obviously written a good deal, perhaps even several years, later.

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Darwin concentrated on about three aspects of the geology of the island:

1. The structure and petrology of Monte Brasil, the steep volcanic cone that almost overhangs the harbour the harbour at Angra.

2. The general nature of the volcanic landscape of the island.

3. The fumaroles, or steam vents, in the centre of the island at Furnas do Enxofre, and the effects of the emerging steam on the surrounding rocks.

All his writings on the geology of Terceira display a strongly comparative approach. Here is his brief account of Monte Brasil from his geological notes:

M. Brazil, close to Angra, is a large & regular crater (part of which the sea has destroyed) which appears entirely to consist of thin layers of brown Volcanic Sandstone, quite similar to those of the Galapagos.- The extremities of the beds overlie the termination of the coast basaltic streams.- So that it is very modern.- Doubtless it is only a dust volcano bursting out beneath water.-

In the Volcanic islands book this had been transformed to:

The town of Angra is overlooked by a crateriform hill (Mount Brazil), entirely built of thin strata of fine-grained, harsh, brown-coloured tuff. The upper beds are seen to overlap the basaltic streams, on which the town stands. The hill is almost identical in structure and composition with numerous crater-formed hills in the Galapagos Archipelago.

The somewhat uncharacteristically dogmatic last sentence of the quotation from the original notes has been omitted. But the accounts of the form of the cone and its crater (in the centre of which, within living memory, crops were grown the traces can still be seen), and the descriptions of the rocks that compose the old volcano are entirely accurate. The grey-brown tuffs, strongly layered, with fragments up to a centimeter or two in diameter, still outcrop clearly on Monte Brasil's flanks. Darwin was always interested in structural geology, and what the relationship between rock masses could tell about the history of the area. Note also the careful comment on the relationship between the Monte Brasil tuffs and the underlying basalts.

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Darwin the geologist had spend long hours during the voyage reading Charles Lyell's Principles of Geology, copies of all three volumes of which he had with him. By September 1836 he had substantial exposure to Lyell's uniformitarian or gradualist ideas, and had applied them in many settings during his journeyings. Lyell's thesis was that the features of the earth's surface were to be understood in terms of gradual, more or less uniform change, through the application of processes that the observer can see around him in the modern world. Lyell emphasized both constructive processes the building up of land through volcanic activity and deposition of sediment and the land's destruction, and removal through erosion. These ideas too, Darwin had taken on board, and in his notes we can see how he noticed evidence of erosion. He observed the very steep seaward face of Monte Brasil, and commented that the sea had "destroyed" part of the hill. His account goes on:

A little further to the Eastward [from Mt Brasil], there is [sic] outlying islands & some rocks which appear of a similar nature, but only a small segment of the crater now remains.

He was referring to the Ilhéus das Cabras, two steep islets, all that remains of a volcanic cone after marine attack, five kilometers due east from Monte Brasil. Darwin would have passed within a little over a kilometre of the islands during his ride eastwards along the coast towards Praia, and the Beagle would also have passed quite close to the islands on arrival at, and on departure from the port of Angra (see Figures 8 and 14).

Elsewhere, describing the narrow valley in the centre of the islands where he observed the steam vents, he wrote that the depression in the ground brought to mind "the washing away & ordinary degradation of the rocks" as much as subsidence. Darwin, now well-equipped with Lyellian, gradualist ideas, was ready to accept the mundane and the gradual rather than the spectacular.

Darwin saw the "big picture" as well as the fine detail, let us look again at some of his notes on the volcanic landforms of the island of Terceira as a whole:

The Islands of Terceira appears to consist of an elevated central part which slopes down on all sides to the sea.- Both on the flanks and on the summit there are scattered numerous volcanic summits.- The streams of lava, which have proceeded from these can in some cases be traced.- And the surface, especially in parts

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of the elevated central land, is covered by hummocky & irregular depressions.- These more modern streams, when I saw then, consist [chiefly] consist of blackish lava. Specimens (3913, 13, 14) show their nature.- Besides these streams there are irregular ridges & large hills composed of a true white or pale grey trachyte … (DAR 38.2/957)

Concisely, if not particularly elegantly, Darwin gives a vivid impression of the somewhat confused hummocky topography of the interior of the island, made up as it is of dozens of intersecting cones, and meandering lava ridges. Along the coast, the dark lava alternates with the lighter tuffs:

On the coast the streams of lava are separated from each other by convoluted layers of tuff, some containing rounded pebbles & being perhaps subaqueous deposits.

The steam vents of Furnas do Enxofre

The steam vents or fumaroles in the centre of the island which he visited the day after his arrival, provided the geological site of greatest interest to Darwin during his stay on Terceira. The three accounts of the site (in the Geological Diary, the general Diary or Journal, and chapter 2 of Volcanic Islands) illustrate well his method of working. They provide examples of careful observation, using a range of senses (feeling, smell and even taste as well as sight), his characteristic comparative treatment, and his attempts at explanation and search for pattern. Darwin frequently reworked his material, both on the Beagle and in later life, adding facts that came to hand later, and integrating material from different sources. Darwin's accounts of the steam vents in the Volcanic Islands volume is thus based on information he recorded in the Diary and in his more specialised geological notes. The more finished account from the book is given here verbatim, but so that the way in which the different sources have been combined can be seen, the other versions are given in Appendix A.

In the central part of the island there is a spot, where steam is constantly issuing in jets from the bottom of a small ravine-like hollow, which has no exit, and which abuts against a range of trachytic mountains. The steam is emitted from several irregular fissures; it is scentless, soon blackens iron, and is of much too high a temperature to be endured by the hand. The manner in which the solid trachyte is changed on the

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borers of these orifices is curious: first the base becomes earthy, with red freckles evidently due to the oxidation of particles of iron; then it becomes soft; and lastly, even the crystals of glassy feldspar yield to the dissolving agent. After the mass is converted into clay, the oxide of iron seems to be entirely removed from some parts, which are left perfectly white, whilst in other neighbouring parts, which are of the brightest red colour, it seems to be deposited in greater quantity; some other masses are marbled with the two distinct colours. Portions of the white clay, now that they are dry, cannot be distinguished by the eye from the finest prepared chalk; and when placed between the teeth they feel equally soft-grained; the inhabitants use this substance for white-washing their houses … . In some half-decayed specimens, I found small, globular aggregations of yellow hyalite, resembling gum-arabic, which no doubt had been deposited by the steam.

As there is no escape for the rain-water, which trickled down the sides of the ravine-like hollow, whence the steam issues, it must all percolate downwards through fissures at its bottom. Some of the inhabitants informed me, that it was on record that flames (some luminous appearance?) had originally proceeded from the cracks, and that the flames have been succeeded by steam; but I was not able to ascertain how long this was ago, or anything certain on the subject. When viewing the spot I imagined that the injection of a large mass of rock, like the cone of phonolite at Fernando Noronha, in a semi-fluid state, by arching the surface might have caused a wedge-shaped hollow with cracks at the bottom, and that rain-water percolating to the neighbourhood of the heated mass, would during many succeeding years be driven back in the form of steam.

Note again the cautious style, typical of Darwin. He carefully separates out what information is based on the reports of others, and of which details he was not certain.

Darwin's slightly understated scientific description (was the perhaps the tiniest bit disappointed that the "so called crater" was not larger?) does not, perhaps, convey the full impression of the scene. I give below my own description, based on field-notes made at the site during my visit in May 1992.

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It is a blind valley, running approximately south-west to north-east, about 150m long and varying from 20 to 30m in width. It is about 20m deep at its steepest part. The ground is open, covered by a tummocky grass, with clumps of Juncus, and Sphagnum where the ground is wet, along with some brambles and bracken. Blackbirds are calling, frogs are croaking in the Sphagnum. The area is traversed by a few ancient drystone walls. The ravine is strongly reminiscent of a valley in Upland Britain the Derbyshire Peak District or parts of Wales, perhaps. On the north-east facing (ie damp) side, in several places, steam emerges from vents. This steam appears more-or-less odourless; the rocks nearby are dripping wet, and covered with dark green algae; the Sphagnum seems to thrive in such places, although in some cases it appears discoloured.

Approximately 80m to the west is a sub-circular crater, c 20m across, and some 10 20m deep. This is much more spectacular: it is almost unvegetated, red/white marbled stone being exposed where it has been affected by the steam. The vents are larger, some of them up to 1m across; some are more or less circular, some irregular in outline, and appear dark and threatening-looking when I peer into them through the drifting steam. The steam appears hotter, and had a faint sulphurous taint, and in places the bright yellow crystals of elemental sulphur can be seen encrusting the rocks. From time to time the breeze shifts in direction, resulting in my becoming engulfed in steam.

In over 150 years some things may have changed, but one feels that the general impression of the place must be must the same. The isolation of the locality, the vivid red and white marbling, the dark irregular fissures, the drifting steam (in his Diary Darwin said that "small jets of steam issued as from cracks in the boiler of a steam engine") all seem to be much the same a century and a half later. Darwin did not specifically mention the sulphur encrustations unless the "small, globular, aggregations of yellow hyalite, resembling gum-arabic … deposited by the steam" refer to this substance. But in one of his accounts he hints at "muriatic acid gas" (ie hydrochloric acid). Very possibly the precise composition of the emerging gas, its temperature, and the exact position of the fissures vary over time. Certainly at the time of my visit there seemed to be some vents that were inactive. See Figures 18 21.

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The upheavals of the past

Darwin visited many volcanic areas in his voyage; in North Island, New Zealand, on the Galapagos, Ascension and Cape Verde he had seen volcanic cones very similar to those of Terceira. But in few places elsewhere had he seen such clear evidence of volcanic activity so close to the surface. It undoubtedly impressed him:

Throughout the island, the powers below have been unusually active during the last year; several small earthquakes have been caused & during a few days a jet of steam issued from a bold precipice overhanging the sea, not far from the town of Angra.

It was in fact from the steep, south-facing slope of Monte Brasil.

In the vague descriptions given to him of flames (mentioned in the account of the fumaroles), and the report that "many years since a large city [Praia] was here overwhelmed by an earthquake" there may linger folk memories of former volcanic eruptions and spectacular quakes. There was in fact an eruption in 1761; other disturbances are recorded from 1614, 1800 and 1801. It is quite possible that Darwin was exposed to garbled accounts of some of these.1 But cautious observer that he was, he interpreted what he was told with care. Of the destruction of Praia he wrote:

Many years since a large city here was overwhelmed by a large earthquake. It is asserted that the land subsided, & a wall of a convent now bathed by the sea is shewn as proof: the fact is probable, but the proof not convincing.

Theories of volcanic Islands

Although the spectacular and the bizarre always had a fascination for Darwin, he was always punctilious in noting his observations of the common and the routine. He thus recorded carefully the appearance of volcanic cones and the igneous rocks that comprised them. Of the uplands north of Angra he wrote:

On every side, besides the ridges of more ancient lavas, there were cones of various dimensions, which yet partly retained their crater-formed summits, & where broken down, showed a pile of cinders like those of an ironfoundry.

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See Figures 3 and 4.

Of the trachytes that formed much of the terrain, in his geological notes he wrote:

. . White or pale grey trachyte full of broken crystals of glassy felspar [sic], brown lines & minute black points precisely similar to the trachyte of Ascension.-

As always, detailed observation, and a careful, comparative approach.

Reference has already been made to Darwin's interest in the general field relations of the main series of rocks. Through his comparative method, he sought to find similarities in these three-dimemsional patterns in different areas, and believed he had found them. He maintained, several times, for example that the typical structure of volcanic islands was a lower, older trachytic core, overlain by more recent basalt flows. Here is his introduction to the section of Terceira in his Volcanic Islands book.

The central parts of this island consist of irregularly rounded mountains of no great elevation, composed of trachyte, which closely resembles in general character the trachyte of Ascension … This formation is in many parts overlaid, in the usual order of superposition, by streams of basaltic lava, which near the coast compose nearly the whole surface.

While still aboard the Beagle he wrote in his notes of the Terceira trachytes:

These lava appeared the most ancient; & their circumstances present the old case of the Trachytic nucleus enveloped by more recent streams of a more basaltic nature. (DAR 38.2/957)

To some extent these conclusions were soundly based, resting as they were on careful observations on several islands, and on shrewd deduction: the "habit of comparison" coming into its own. But Darwin spent less than a week on Terceira, and his visits to many of his other volcanic island sites were also fairly brief, and so it is hardly surprising if his view was incomplete or oversimplified. One recent summary2 of the geological history identified the following:

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1. Pre-trachyte basaltic and "andesitic" complex, subdivisible into three distinct phases.

2. The trachytic eruptions.

3. The quaternary basalts.

4. Historic eruptions.

Some geologists who have studied the petrology of the Azores also stress that Terceiran lavas display considerable mineralogical and geochemical variety. The term "hawaiite" (or trachybasalt) has been used for some lavas, and olivine basalts occur. A few basalts on Terceira have been described as "hypersthene normative". It has also been shown that Terceira basalts have a quite distinctive isotope signature appreciably different from those of the nearby islands of São Miguel and Faial.3

Bearing in mind the very limited amount of training in mineralogy and petrology Darwin had, and the simplicity of his field equipment probably not much more than a geological hammer and a hand lens, his rock identification was pretty good.

But when summarizing his findings from all the volcanic islands he had visited during the voyage in his Volcanic Islands volume he does more than suggest the simple modes of their structure that consisted of an older core or nucleus of trachyte, and an upper layer of younger basalts. He offered an explanation of the variety of rock types on volcanic islands. His idea was that under certain circumstances, in a mass of molten rock the heavier minerals would separate out:

The sinking of crystals through a viscid substance like molten rock as is unequivocally shown to have been the case in the experiments of M Dree, is worthy of further consideration, as throwing light on the separation of the trachytic and basaltic series of lavas.

Once again Darwin's views were something of an oversimplification, but were nevertheless far ahead of his time. The process now identified as being responsible for the derivation of a variety of rock-types from a single melt is fractional crystallisation. The crystallisation of minerals in a particular order from a melt (of given chemical composition and under given given conditions of temperature and pressure) results in the formation of a residual melt of very different chemical composition from the original magma. One common fractionation path does in fact lead

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from basalt to trachyte. Darwin, according to modern petrological interpretation, would seem to have been in error in emphasising his gravity mechanism alone, but correct in his speculation about the derivation of trachyte and basalt from the same parent melt, and correct in suggesting that crystallisation has something to do with the differentiation process.

But there is much more. Darwin, in his wanderings was impressed by the way in which remote oceanic islands were almost always composed of volcanic or coral-rock material. True, sedimentary rocks were extremely rare. Terceira was quite typical. Also, sailing along the coast of Terceira, and a day or so later, along that of São Miguel, and then in the years that followed as he pored over hydrographic charts and maps of the archipelagoes of the world Darwin was struck by the alignment of the cones on the individual islands, and of islands in archipelagoes. Darwin comments on these facts in chapter 6 of his book:

The composition of the numerous islands, scattered through the great oceans, being with such rare exceptions volcanic, is evidently an extension of that law, and the effect of those same causes, whether chemical or mechanical, from it results that in a vast majority of the volcanos [sic] now in action, stand either as islands in the sea, or near its shores. This fact of ocean islands being so generally volcanic, is, also, interesting in relation to the nature of mountain-chains on our continents, which are comparatively seldom volcanic; and yet we are led to suppose, that where our continents now stand, an ocean once extended. Do volcanic eruptions, we may ask, reach the surface more readily through fissures, formed during the first stages of the conversion of the bed of the ocean into a tract of land?

After specifically mentioning the arrangement of the islands of the Azores into lines, he goes on:

[We are struck] … when viewing on a map of the world, how perfect a series exist, from a few islands placed in a row, to a train of linear archipelagos following each other in a straight line, and so on to a great wall like the Cordillera of America …

… but if trains of linear archipelagos are in the course of time, by the long continued action of the elevatory and volcanic forces, converted into mountain-ranges, it would naturally result, that the inferior primary rocks would often be uplifted and brought into view.

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Again Darwin was mistaken in some major respects. But the ideas of modern plate tectonics and sea-floor spreading lay 120 years in the future. And yet Darwin speculated that oceanic volcanic islands might lie on fissures where the bed of the ocean was being converted to a tract of land, and that "lines of islands" might have something to do with the formation of mountain ranges! He does not use the term "island arcs" but he does observe that many "chains of islands" are curved or arcuate! He was uncannily perceptive in a number of ways.

Figure 15. Lava flow exposed in road cutting, south coast of Terceira, near Anga do Heroismo.

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Figure 16 (above). Lava from road cutting near São Judeu. Darwin felt that this type of of rock resembled "cinders like those from an confoundry". Figure 17 (below). Mottled red-white clay from near the steam vents. Scale in mm.

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Figures 18 and 19. The steam vents of Furnas do Enxofre.

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Figures 20 and 21. The steam vents of Furnas do Enxofre (continued).

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Figures 22 and 23. Terceira countryside and village. Above: "The land is well cultivated & is divided into a multitude of rectangular fields by stone walls." Below: "Small hamlets and whitewashed houses are scattered in all parts."

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Chapter 4

Countryside, Town and People

The island [of Terceira] is moderately lofty & has a rounded outline with detached conical hills of volcanic origin. The land is well cultivated, & is divided into a multitude of rectangular fields by stone walls, extending from the water's edge to high up on the central hills. There are few or no trees, & the yellow stubble land at this time of year gives a burnt up & unpleasant character to the scenery. Small hamlets & single white-washed houses are scattered in all parts. (Diary)

The above are Charles Drawin's initial impressions of the island, probably written during the visit. They are in many respects typical: he summarises the essential "feel" of a scene with economy, but yet very vividly. He appreciates that what he sees is the result of the subtle interplay of human actions on the physical landscape. He is quite happy to allow his own appraisal to intrude on objective description he frequently make it clear in his writings what he regards as an attractive view. Note that the fields are well cultivated, but that the burnt up stubble gave the landscape a "burnt up" and unpleasant appearance views that to some extent reflected the middle-class English landscape tastes of his day.

There was indeed quite a lot about the people and their way of life of which he approved. He refers to the local country people as being "happy" or "industrious", and the sight of them going about their daily work as being "pleasant". Here is a typical passage:

Their clothes although very ragged, appeared singularly clean, as well as their persons; I am told that in almost every cottage a visitor will sleep in snow white sheets & will dine off a clean napkin … . Their ruddy complexion, bright eyes & erect gait, made them a picture of a fine peasantry.

Hard work, cleanliness, politeness and good health are characters that the young Englishman values: unsurprising, perhaps, considering the Protestant, upper-middle class stock from which he came.

No detail of the local folk's appearance or way of life escaped him:

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Each man carries in his hand a walking staff about six feet high; by fixing a large knife at each extremity, they can make this into a formidable weapon.

The bizarre and unusual always appealed to Darwin; here is the sort of little snippet about the people's way of life in which he rejoiced:

The harvest was lately over, & near to the houses the fine yellow heads of Indian corn were bound for the sake of drying, in large bundles to the stems of the poplar trees. These seen from a distance appeared weighed down by beautiful fruit,- the very emblem of fertility.1

There were other crops that he noticed during the Azores visit. The north-east of the island was "particularly well cultivated" and produced "a large quantity of fine wheat". He also mentions vineyards. São Miguel, that the Beagle visited a day or so after leaving Terceira, produced oranges. A large fleet of ships exported "numberless" fruit to England. Although "several hundred vessels" were loaded with oranges "these trees on neither island appear in any great numbers."

Darwin often writes sympathetically about poverty and its causes. By this stage in his journey he had seen numerous peasant cultures, and in accordance with his oft-used comparative approach, compared the various human societies he had seen:

… how different [are the people of the Azores] from the Portugueese [sic] of Brazil! The greater number which we this day met, were employed in the mountains gathering sticks for firewood. A whole family, from the father to the least boy, might be seen each carrying his bundle on his head to sell in the town. Their burthens were very heavy; this hard labour & the ragged state of their clothes, too bespoke poverty, yet I am told it is not want of food, but of all luxuries,- a case parallel to that of Chiloe. Hence, although the whole land is not cultivated, at the present time numbers emigrate to Brazil, where the contract to which they are bound differs but little from slavery. It seems a great pity that so fine a population should be compelled to leave a land of plenty, where every article of food,- meat, vegetables & fruit,- is exceedingly cheap & most abundant; but the labourer finds his labour of proportionally little value. (Diary)

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In his descriptions of human societies, just as with geological features or living things, we see the fine eye for detail, the comparative method, something of an analysis of relationships (for example that between the cost of living and wage-rates), as well as a hint of an attempt at explanation - he at least implies that the poverty is due to a high level of population in relation to the resources. And he later writes of a large part of the centre of the island as being "not inhabited, & bears a desolate appearance", a description that is still accurate.

Darwin also frequently mentions the physiognomy and physical appearance of the folk he saw a legacy perhaps of his days as a medical student. He does not give many such details of the people of Terceira, but the following trifle is perhaps of interest:

A surprising number of boys had white or lightly coloured hair, which from its strangeness to our eyes made it the more pleasing.

Blonde persons, children or adults, are rare in the streets of the very Portuguese city of Angra today most of the population have characteristically southern European dark hair and the fragment is difficult to explain. In the Diary it is deleted, so perhaps Darwin later, after seeing more of the people of the island, thought better of the observation, possibly realising that some first impression was not typical.

Darwin's description of the two urban settlements of Terceira is rather brief, but again shows Darwin taking an interest in almost everything he saw, and recording it accurately. His account of Angra although succinct, catches the feel of the place:

[T]he town or rather city of Angra, [is] the capital of the neighbouring islands. We found the city a very clean & tidy little place, containing about 10,000 inhabitants, which includes nearly the fourth part of the total number on the island. There are no good shops, & little signs of activity, excepting the intolerable creaking of an occasional bullock waggon [sic]. The churches are very respectable, & there were formerly a good many convents … Angra was formerly the capital of the whole archipelago, but it has now only one division of the islands under its government, & its glory has departed. The city is defended by a strong castle & line of batteries which encircle the base of Mount Brazil, an extinct volcano with sloping sides, which overlooks the town.

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The creaking bullock wagons have been replaced by a confusion of modern cars in the grid-like network of narrow streets in Angra, and there are plenty of (often rather small) shops to cater for the whims of a quite prosperous urban community, but much of the remainder of the description is still accurate. The "fine churches", literally dozens of them,2 still dominate the townscape (see Figure 25). The population of the city still represents a substantial proportion of that of the island (about 20,000 out of 60,000). And Darwin uses the right word when he refers to the "tidy" city. Travellers for generations have used this word to describe Angra. It is well-kept, clean, and the urban form is on a human scale. The streets are narrow, yet somehow, perhaps because of the innate good naturedness of the people, the worst excesses of traffic congestion are avoided. Few of the buildings (apart from the "fine churches") are more than three stories high. Despite wars and civil strife, and the effects of intermittent earthquakes, the buildings are mostly well-painted and in good repair. Many of the houses are several centuries old, and despite the ravages of time, a number of the buildings that Darwin passed in 1836 are the same as those that the visitor enjoys today (see Figure 24).3 The modern visitor too, would agree that the presence of the wooded slopes of the steep Monte Brasil contributes to the picturesqueness of the city.

By September 1836 Darwin was something of a connoisseur of fortifications and military architecture. He had shared his cramped quarters for five years with experienced and knowledgeable naval officers. He had come close to a firefight in South America. He comments in his writings approvingly on the defences of some of the South American cities he visited, and compared those of some of the Australian settlements, such as Hobart Town, most unfavourably with these. He knew what he was talking about.

Darwin's "strong castle" was probably São Sebastião Castle, overlooking Porto de Pipas, immediately to the east of the little bay that forms the harbour; it has a squat, square, form, with thick stone walls, and was built atop an eminence from which the shipping could be surveyed, at the direction of King Sebastião in the 16th century. Although the building now houses the port administration, it was in military use until relatively recently. Indeed, following the Anglo-Portugese Treaty signed in August 1943, it provided the base for the first British military presence in the Azores that was established in October of the same year. See Figure 26.

The other part of the impressive system of fortifications lies to the south-west of the old core of the city, at the foot of Monte Brasil. The

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works here have been described as one of the most important sets of fortifications in Europe dating from the sixteenth and seventeenth centuries. A truly massive set of defensive walls and bulwarks faces to the north and east, preventing access to the peninsula formed by the mountain itself. Bastions, arrowhead shaped in plan, confront the intruder from the direction of the city. An impressive gate in worked stone provides access to the São João Baptista Castle within. The castle was built by the Spaniards during their occupation of the islands, and besides having been used to store wealth brought by the galleons, has also held some distinguished prisoners, including King Afonso VI from 1669 to 1675, and, in the nineteenth century, the Mozambican Chief Gungunhana, and his entourage. See Figures 27 and 28.

Darwin's note that Angra was originally capital of the whole of the Azores archipelago, and latterly only the central group of islands, and that this had been responsible for something of a decline, was also correctly based.

The much smaller town of Praia, 15km to the north-east of Angra, did not detain Darwin long; he thought it "a quiet forlorn little place", an impression shared by many modern visitors (although the construction of a new port facility should bring employment to the sleepy town). He was more interested in the evidence it provided of the effects of earthquakes, and sea level change, than in the churches and the old houses in the narrow streets (see chapter 2).

After remarking on the "fine churches", in Angra, and the fact that there had formerly been a number of converts, Darwin comments:

Dom Pedro destroyed several; he levelled three nunneries to the ground, & gave permission to the nuns to marry, which, excepting by some of the very old ones, was gladly received …

Terceira was the first place that received Dom Pedro, & from this beginning he conquered the other islands and finally Portugal. A loan was scraped together in this one island of no less than 400,000 dollars, of which not one farthing has ever been paid to these first supporters of the present right royal & honourable family.

Darwin was not always at his best when it came to history, but the account above seems accurate in many respects.

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He appears surprisingly matter-of-fact about the "levelling" of the convents and the turning out of the nuns: events that occurred just four years before his visit, in 1832. But it must be recalled that in the 1820s Portugal was ruled by "absolutists", a reactionary, dictatorial group with strong support from the Catholic clergy. Britain, with a number of other European powers, worked to establish a constitutional, parliamentary government, and indeed in 1827, a British force landed at Lisbon in support of these aims, withdrawing fifteen months later. Dom Pedro, although he had held the throne of Brazil, and was a member of the Portuguese royal house, identified strongly with the constitutional party. Moreover, religious tolerance was still a young, weak flower in England. The Catholic Emancipation Act, which allowed those of Roman Catholic faith to vote, stand for Parliament and hold military commissions had only been passed in 1829, and many restrictions still remained. Amongst the officers on the Beagle, support for Dom Pedro, even to the extent of destroying convents, might have been quite strong. After his years amongst them, the "whiggish" young Darwin might have absorbed some of these values. This perhaps explains Darwin's almost eulogistic reference to "the present right royal & honourable family". But to be fair, some implied criticism is incorporated in the suggestion that they had not paid back what they owed to their supporters on the island!

Darwin's eye for detail, his comparative turn of mind, his remarkably integrative, and analytical approaches, are to be seen in his accounts of human communities and cultural landscapes. Like everyone else, he saw the world through the lens of his own cultural values, background and training. Although to some extent his views reflect those of his day and personal situation, we see Darwin in Terceira in September 1836, at the end of a voyage that had presented to him a tremendous range of societies and lifestyles, as interested as ever in people and their lives, and concerned about their difficulties.

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Figure 24. Part of the Old Town of Angra. Some of the houses in the "tidy town" date from the early years of the eighteenth century.

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Figure 25. One of Angra's "fine churches": the church of the Misericórdia.

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Figure 26. São Sebastião Castle.

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Figures 27 and 28. Fortifications at the foot of Monte Brasil

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Chapter 5

Echoes of Home

In his letters home in the last few months of his sojourn aboard HMS Beagle, Charles Darwin makes it very clear that he was looking forward eagerly to the end of the voyage.1 He detested the sea for he was frequently seasick. Moreover, he had been ill with mysterious complaints, perhaps more serious than seasickness, while in South America, and as late as his stay in Cape Town, he had been purchasing drugs.2 He had lost quite a lot of weight during the voyage. Probably the by now twenty-seven year old naturalist was feeling that nearly five years at sea, with its long periods of confinement, and restricted diet, was more than enough, despite the friendships that he had made. Possibly the longing for home and things familiar grew more intense as they became closer to view. Oftimes one has the feeling that it is just before its conclusion that an unpleasant experience becomes particularly intolerable! Several times in his notes and letters written at the Cape of Good Hope there are nostalgic references to "shady lanes", as he compares the dry fynbos vegetation to the cool, green landscapes of home.3 Parts of the Isle of St Helena (the landfall after the Cape) he compared wistfully to the uplands of Wales. The Azores archipelago he anticipated with some pleasure (see chapter 1), but possibly in part because it was the last port of call before Albion was regained.

Perhaps for these reasons, therefore, during his stay on Terceira, Darwin was particularly alert to similarities with Britain. His first morning ashore had him riding inland from the port of Angra "in deep lanes bordered on each side by high stone walls" (see Figure 9). A few lines later he continues, in his diary:

The rocks are covered in some parts by a thick brushwood about three feet high, & in others by heath, fern and short pasture: a few broken down old stone walls completed the resemblance to the mountains of Wales.

Darwin was perhaps thinking of those days in North Wales, the summer before he left Britain, where at the hand of Professor Adam Sedgwick, he received the only formal instruction in geology he ever had.

On another day he was viewing a very different, flatter, landscape in the north-east of the island.

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The square, open fields, & small villages with white washed churches, gave to the view, as seen from the heights, an aspect resembling the less picturesque parts of central England.

Maybe he was recalling the landscapes of the Midlands - Bedfordshire or Northamptonshire perhaps with their reticulate network of field boundaries that he had traversed on his journeys between his home in Shrewsbury and Cambridge (see Figures 5 and 22).

It was not just the landscapes that provided reminders of his homeland:

I saw, moreover, some old English friends amongst the insects, & of birds, the starling, water wagtail, chaffinch & blackbird.

The visitor to Terceira from England in the 1990s has almost the identical experience. In the Azores in May, as Tennyson put it in Early Spring

The blackbirds have their wills

as they sing from the boulders and drystone walls in the green, island landscape. Starlings still sing tunelessly but wholeheartedly from cottage roofs, and chaffinches, with a slightly different dialect from those of lowland England, throw their songs to the air in the laurel woodlands of Monte Brasil. The identity of Darwin's "water wagtail" is not quite so clear, partly because the taxonomy of the genus Motacilla is somewhat complex, with considerable variability within what are sometimes regarded as species, sometimes as races. There is a measure of confusion about both the common and scientific names. The name "water wagtail" is avoided by modern ornithologists and is not found in many current field guides. But many books published in the earlier decades of this century, and before, use it for the pied wagtail Motacilla abla (for which the names white, and Yarrell's wagtail have also been sometimes used in the past, although some authors attempted to use the names for different races). The name "yellow water wagtail" is known from The ornithology of Francis Willurghby (1678) for the yellow wagtail, M. flava;4 the name blue-headed wagtail is also used for some races of this species. The most conspicuous wagtail on Terceira at the time of my visit was the grey wagtail, M. cinerea, which has a yellow plumage superficially similar to M. flava. This species fluttered around water in puddles and horse troughs on the edge of Angra, and was to be seen in the open ground between the town and the battlements around the foot of Monte Brasil (localities that may well have been visited by Darwin, incidentally), and this is another alternative. Whichever species

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it was, it would have been familiar from his ramblings in the English and Welsh countryside, for all three occur in Britain. Other birds now common on the islands include the robin, house sparrow, goldfinch the avifauna would have seemed comfortable and familiar after the strangeness of the bird faunas of South America, Africa and Australia.5

Darwin's familiarity with Terceira's biota is perhaps further illustrated to some extent, in that he took no natural history specimens (apart from rocks). A keen beetle collector since his schooldays, he accumulated thousands of insect specimens on his Beagle voyage, although none from the Azores. Possibly the "old English friends amongst the Insects" were so familiar to him that he did not consider it worthwhile taking special written note of them, let alone collecting specimens. Today the visitor from the British Isles notices several butterfly species (Browns, Whites) and bumblebees that appear familiar from gardens at home, and it might have been creatures such as these that he noticed.

Darwin is equally casual about the plant species, mentioning in passing poplar trees (still common on Terceira), and "fern" (probably bracken); he also uses a few general terms such as "heath", "short pasture" and "brushwood". Certainly some of the plants and plant communities would have a familiar look to them.6

Darwin's attitude to the Azores is probably summarised in his last remarks on Terceira:

When we descended to the city, I heard the good news … that we should go to sea the same evening.

and on departing from the island of São Miguel a day or so later:

[W]e steered thanks to God, a direct course for England.

There were things that Darwin quite liked about Terceira, and the green familiarity of parts of the landscape, along with the (to him) commonplace organisms that lived there were amongst them. It reminded him of home in so many ways, yet it was not home, and he was glad to be away.

Immediately after Darwin's last diary entry on the Azores, probably written in the few days of sailing between São Miguel and Falmouth, is his summary of "the advantages and disadvantages, the pains & pleasures, of our five years' wandering":

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No doubt it is highly satisfactory to behold the various countries, & the many races of mankind, but the pleasures gained at the time do not counterbalance the evils. It is necessary to look forward to a harvest however distant it may be, when some fruit will be reaped, some good effected. Many of the losses which must be experienced are obvious; such as the society of friends, & of the sight of those places, with which every dearest remembrance is so intimately connected. These losses, however, are at the time partly relieved by the exhaustless delight of anticipating the long-wished for day of return. It as poets say, life is a dream, I am sure in a long voyage these are the visions which best pass away the long night. Other losses, although not at first felt, after a period tell heavily; these are the want of room, of seclusion, of rest; the jading feeling of constant hurry; the privation of small luxuries, the comforts of civilisation, domestic society, & lastly even of music & the other pleasures of imagination.

Here is a man who has completed the main collecting and observing phase of his life's work, looking back on the hardships endured, appreciating that he was but a few days from his home and family awaiting him is Shrewsbury.

Figure 29. Blackbird (Turdus merula) at nest. Photo: the late Edward Armstrong

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Concluding Summary

The visit to the Azores came at the end of the Beagle's five year voyage, and it is interesting to compare Darwin's methods of working with those he adopted at other ports of call.

In many respects his approach remained remarkably constant throughout the voyage, and the nature of his observations at Terceira were very similar to those he made elsewhere. He showed a strong interest in geology, and the observations he made in the Azores, both at the time and later, were fitted into broad, and for their day, quite enlightened theories; by the end of the voyage Charles Darwin was building sophisticated conceptual structures and attempting to arrange his material upon them. Terceira was of particular interest in that it was one of the few localities he visited where some residual thermal activity was present. He displayed, at Terceira, a real interest in his fellow humans, and as at localities in South America, Australia. New Zealand, the Cape of Good Hope and Cocos, was a vigorous social critic. He also shows a feeling for the "dialogue" in which the human community engages with its environment, and the cultural landscape that results. In Terceira he again used the comparative approach that he used throughout his journey.

A little strangely, in view of his interest in island biotas, his observations on natural history were sparse. He recognised some birds, insects and plants, but he made no study of the marine organisms as he had done, for example, at East Falkland, Cape Verde and the Cocos (Keeling) Islands. Apart from half-a-dozen rocks, he collected no specimens. He seems to have made errors in his dates (see Appendix B); this last point may not be significant he made other errors during his travels but it might suggest he was getting a little careless.

A theme that runs through a good deal of what he wrote on Terceira was a certain homesickness. The Azores were the last landfall before Falmouth. In the blackbirds amidst the laurel bushes, the flicking of the wagtails' feathers as the small birds searched for insects, and in some of the smaller creatures of the countryside there were echoes of the familiar, and he wanted to be home. Finally he knew that a certain stage of his life's work was complete and he wanted to move on to the next the sorting of his specimens, the thoughtful evaluation of what he had seen, and the writing-up of his findings.

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In the archival record, and in what is missing from it, for Darwin's stay at Terceira we see, perhaps more clearly than in that for other locales visited during the Beagle voyage, the human face of the naturalist at work.

The eye for detail was still there, and his mind was as curious as ever integrating, comparing, seeking explanations, building theories. But here also is a man who was tired of voyaging, who longed for home and family, and who occasionally made mistakes.

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Appendix A

Charles Darwin's Accounts of the Steam Vents at Furnas do
Enxofre

Darwin wrote three accounts of the fumaroles or steam vents at Furnas do Enxofre that he visited on his first full day on Terceira. These comprised his notes in his Geological Diary, his entry in his general, personal Diary or Journal, and his fullest, most polished account, based upon these two, his description in chapter 2 of Volcanic Islands, volume 3 of The Geology of the Voyage of the Beagle. The text of the last of these was included in chapter 3. So that this final version can be compared with the two earlier sets of observations, these are given here.

Geological Diary

In the Centre of the island there is a spot where boiling hot steam issues in considerable quantities.- There is a slight hollow, or little valley (like an ancient stone quarry, the bottom of which is traversed by several wide fissures. The neighbouring rocks are all [fine del] trachyte, & not particular cellular.- The action of the steam, which is mingled with some acid vapour has acted on the rocks in a most singular Manner & reduced them to clay. The steam issues in nearly a dozen places through hot & moist clay.- This latter substance varies suddenly in its colour, one part being snow white*, another bright red, like Vermilion, & a third the two kinds Marbled together. The Trachyte, which has been only partly altered, the whole is mottled with minute red speck which evidently is the oxidised iron.- In some fragments this substance is so abundant, that the Trachyte is the colour of a brick.- The sudden & complete variations of colour of the perfectly decomposed stone or clay must be owing I suppose [is that del] to the iron being gradually dissolved in certain parts & again precipitated in others.- The water from the surrounding banks when it rains must penetrate the [neighbour del] the fissures at the bottom, for there is no exit from the hollow.- It is singular that the fissures appear as if the softened rock was degraded & then then [sic] carried away.- But where can it go? Is there a subterranean cavity.

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Note on next page:

*This white Porcelain Clay is used for whitewashing the houses &c. DAR 38.2/960

Darwin's suspicion that there were underground cavities in the area was correct. There is a large cavern, sometimes now open to the public, a little over a kilometre to the east of Furnas do Enxofre, at Algar do Carvão.

Dairy or Journal

When we reached the so called crater, I found it a slight depression, or rather a short valley abutting against a higher range & without any exit. The bottom was traversed by several large fissures, out of which in nearly a dozen places, small jets of steam issues as from the cracks in a boiler of a steam engine. The steam close to the irregular orifices is far too hot for the hand to endure it; it has but little smell, yet everything made out of iron being blackened, & from a peculiar rough sensation communicated to the skin, the vapour cannot be pure, & I imagine it contains some muriatic gas. The effect on the surrounding trachytic lavas is singular, the solid stone being entirely converted either into pure snow white porcelain clay, or into a kind of bright red, or the two colours marbled together: the steam issued through the moist & hot clay. This phenomenon has gone on for many years; it is said that flames once issued from the cracks. During rain, the water from each bank must flow into these cracks; & it is probable that this same water, trickling down to the neighbourhood of some heated subterranean lava, causes this phenomenon.

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Appendix B

Possible Errors in the Dates in Darwin's Diary

In his Diary Darwin states that it was on the morning of September 20th 1836 that the Beagle was "off the East end of the island of Terceira" and "a little after noon on the same day" the ship came into the harbour at Angra. He reports later that it was on "the next day" that he visited the fumaroles of Furnas do Exnofre (ie on 21 September on his reckoning).

His entry for 24th September commences "In the morning we were off the Western end of St Michael's …". As there are no entries between his entry describing the late afternoon departure from Terceira, by his dating the ride to Plaia and across the mountains, and the Beagle's leaving Angra must have been on 23rd.

Of the "24th" he writes: "A contrary wind delayed us all day". He continues, "but by the following morning (25th) we were off the city & a boat was sent on shore".

The Log of the Beagle, which was regularly countersigned by Captain FitzRoy, give daylight on Monday 19th September 1836 as the first time the island of Terceira was glimpsed. Interestingly Syms Covington's Diary (which gives very little detail about the visit otherwise) confirms this.

The Log also states that it was on 22 September that the ship "weighed and made sail" from the exposed little harbour at Angra, and early morning of 23rd that the Beagle was off the westernmost point of São Miguel (St Michael's) for the first time, that they then were indeed "taken aback", but that it was late in the afternoon of the same day that the ship's boat returned from a search for letters, and they finally departed from the Azores.

It is almost inconceivable that the official ship's log could be in error. On the other hand as Darwin wrote up his diary intermittently, often some days afterwards, it is quite possible that he made mistakes. This is not the only occasion that his chronology appears incorrect.

My interpretation is that he was a day out at the start of the visit and that he was consistently one day wrong for the days the ship was at Terceira. Then, when he wrote up his diary a few days later, remembering

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the day languishing at sea off São Miguel, he mistakenly introduced another day. As, he had no further diary entries apart from his few paragraphs of final recapitulation of the voyage (see chapter 5) he might never have had cause to check his chronology carefully.

I give below my reconciliation of the dates of the chronology the Log, and that Darwins's Diary. Not all events are mentioned in both there was of course no reason that the official log should record Darwin's peregrinations and the date of the Monte Brasil visit is not expressly stated anywhere:

Event Beagle Log Darwin's Diary
First glimpse of Terceira 19 September 20 September
Arrival in Angra 19 September 20 September
Trip to fumaroles 20 September 21 September
Monte Brasil excursion 21 September 22 September
Trip to Praia 22 September 23 September
Departure from Angra 22 September 23 September
First glimpse of São Miguel 23 September 24 September
Departure from São Miguel 23 September (late afternoon) 25 September

In this work I have used the Log chronology in preference throughout.

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Notes and References

Introduction

1 Armstrong, P H, Charles Darwin in Western Australia: a young scientist's perception of an environment, Nedlands, University of Western Australia Press, 1985.
Armstrong, P H, Darwin in Mauritius: natural history, landscape and society, Indian Ocean Review, 3(4), 11-13, 1990.
Armstrong, P H, Three weeks at the Cape of Good Hope in 1836: Charles Darwin's African interlude, Indian Ocean Review, 4(2) 8-13, 19, 1991.
Armstrong, P H, Under the blue vault of heaven: a study of Charles Darwin's sojourn in the Cocos (Keeling) Islands, Nedlands, Indian Ocean Centre for Peace Studies, 1991.

Arsmtrong, P H, Darwin's desolate islands: a naturalist in the Falklands 1833 and 1834, Chippenham, Picton Publishing, 1992.
Arsmtrong, P H, Charles Darwin's visit to the Bay of Islands, December 1835, Auckland Waikato Historical Journal, 60, 11-24, 1992.
Arsmtrong, P H, Charles Darwin's perception of the Bay of Islands, New Zealand 1835, New Zealand Geographer, in press.

2 Barlow, N, (ed) Charles Darwin's Diary of the Voyage of the Beagle, Cambridge University Press, 1933. (A new transcript of the Diary was published in 1988.)

3 Darwin wrote many hundreds of pages of geological notes during the voyage. They are to be found in the Darwin Archive in Cambridge at DAR 32-38 inclusive.

4 DAR 223. Letter: Charles Darwin to Caroline Darwin; Bahia, Brazil, 4 August 1836. Published in Burkhardt, F, and Smith, S, (eds) The correspondence of Charles Darwin: volume 1, 1820-1836, Cambridge University Press, 1985. The forthcoming visit to the Azores is also briefly mentioned in a letter to Darwin's friend and teacher, the Reverend Professor John Stevens Henslow; St Helena, 9 July 1836. The original of the latter is held at the Royal Botanic Gardens, Kew.

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5 ML MSS 2009/108, item, 5.

6. Darwin, C, The geology of the voyage of the Beagle, volume 2, Geological observations on volcanic islands, London, Smith Elder and Co. 1844.

7 FitzRoy, R. Narrative of the surveying voyages of His Majesty's Ships Adventure and Beagle, 1826-1836 … ., London Henry Colburn, 1839.

8 Carmichael, I S E; Turner, F J; Verhoogen, J, Igneus petrology, New York, McGraw-Hill, pp 389-392, 1974.

Davies, G R; Norry, M J; Gerlach, D C; Cliff, R A, A combined chemical and Pb-Sr-Nd isotope study of the Azores and Cape Verde hot-spots: the geodynamic implications, pp 231-255, in Saunders, A D, and Norry, M J, Magmatism in the ocean basins, Geological Society Special Publication No 42, Oxford, Blackwell Scientific Publications, 1989.

9 Originally simply Angra, the title "Heroismo" (Heroism) was added by Queen Maria, II, in the middle of the nineteenth century, following the Civil War, at the suggestion of the writer Almeida Garrett.

10 The name Vila da Praia de Vitória was conferred on the town in 1837 following the town's heroic and successful resistance to a landing by an absolutist fleet in 1829.

11 The general aspect of the island's flora is European. Thus in the course of a short stroll on the outskirts of Angra I encountered such typical general of the English countryside as Pteridium, Rubus, Taxaxacum, Papaver, Plantago, Vicia and Urtica as well as a number of species of European grasses. However, amongst several taxa with African affinities I noticed Mesembryanthemum; a Callistemon (bottlebrush) growing close to the summit of Monte Brasil, an Araucaria and several species of Eucalyptus, reminded me of Australia. Opuntia was among a number of North America species. Asia was represented by thickets of bamboo.

Chapter 1

1 See Introduction, note 4.

2 Diary; see Introduction, note 2.

3 A list of the books aboard the Bealge is given in Appendix 4 of Burkhardt Smith (1985), see Introduction, note 4.

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Chapter 2

1 Diary

2 Ibid

3 Ibid

Chapter 3

1 There have also been several new islands formed by volcanic activity within the last two centuries. One appeared just off Ponta Ferrariá, West of São Miguel in 1811. It reached 125m (41 feet) in height but was then eroded away, completing its entire life cycle in 119 days (18 June 15 October). Its life history was documents by Captain Tilliard of HMS Sabrina (Philosophical Transactions, 1812). In 1867 another volcano rose from the sea 21km (12 miles) north-west of Terceira. It too soon became inactive and was removed by the sea.
The effects of the 1980 earthquake can be seen in the occasional tumbledown or damaged building, both in the city of Angra, and in the Terceiran countryside.

2 Comité National Francis de Géologie, Geologie de pays euopéens (Espagne, Grèce, Italie, Portugal, Yougoslavie), Paris, Dunod, 1980.

3 See Davies, Norry, Gerlach, and Cliff (1989), Introduction, note 8.

Chapter 4

1 Diary. The heads of Indian corn are still put out to dry; today however, they are stacked on pyramidal racks made from poles and laths, rather than being attached to poplar trees. The laden pyramids close to cottages constitute a conspicuous element in the Terceira countryside (see Figure 30). But poplar trees remain common.

2 The "fine churches" remain one of the joys of the city of Angra. The positions of some of them are shown in the sketch-map in Figure 8. Several date from the sixteenth or seventeenth centuries, sometimes incorporating parts of earlier buildings. Impressive gilded woodwork is a feature of the interiors of several.

3 A small house in a street close to the harbour conspicuously bears the date 1705.

The architectural heritage, and distinctive character of the city of Angra do Herosimo has been recognised by the granting by UNESCO of

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International Heritage Site status to the entire central area. This provides international recognision of its conservation status and heritage values. Substantial European Community support has been given to the preservation of the city's architectural and historic monuments.

Chapter 5

1 See chapter 1.

2 In Cape Town he bought carbonate of soda, laudanum (tincture of opium) and "lozenges".

3 See Armstrong (1990), Introduction, note 1.

4 Smith, S, The Yellow Wagtail, London, Collins, 1950.

5 The uniqueness of island biota was a subject of particular interest to Darwin, and he would have been interested to know that there is a distinct Azorean race of the bullfinch (Pyrrrhula pyrrhula murina). This could be found, although it was not abundant, in the woodlands covering Monte Brasil in 1992. Much commoner is the canary (Serinus canaria) a characteristic species of the Azores and, of course, the Canary Islands.

Figure 30. Pyramidal racks for the drying of Indian corn

[page 65]

[back cover]

Charles Darwin visited many islands and archipelagoes during the voyage of the Beagle around the world during the years 1831-1836. Although the visit to the Galapagos Islands off South America is the best known of these visits, the young naturalist's sojourns at a number of these tiny spechs of land had important influences on his development. Terceira on the Azores was the last of these, and although there are signs that he was getting tired of journeying, he was in many ways observing, describing and interpreting his environment in much the same way that he had at the many previous ports of call. This book, illustrated by photographs of many of the sites visited by Darwin as they appear today reconstructs in detail his itinerary, and describes how he percieved and interpreted this environment, using a ranges of archival sources.

Patrick Armstrong teaches geography at the University of Western Australia, and has written a number of books and articles on the life and work of Charles Darwin.


Geowest No 27
Department of Geography, University of Western Australia
1992

ISBN 0 909678 359


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Citation: John van Wyhe, editor. 2002-. The Complete Work of Charles Darwin Online. (http://darwin-online.org.uk/)

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