RECORD: Darwin, C. R. 8.1836. [Beagle field notes] 'Bahia Brazil Aug: 1836'. CUL-DAR38.954-956. Transcribed by Kees Rookmaaker. (Darwin Online,

REVISION HISTORY: Transcribed by Kees Rookmaaker, proofread and corrected by John van Wyhe and Gordon Chancellor 9.2009, editorial editions by John van Wyhe 10.2015. RN5

NOTE: These field notes are written on three folios. The paper has a bluish tinge, measuring: 954 is 20 x 27 cm; 955 is 20 x 31.8 cm; 956 is 15.5 x 20 cm (lower part excised). The text is written in pencil except where otherwise noted. Part of the text on the edges of the document is obscured by archival tape.

Normally Darwin entered field notes during the Beagle voyage in his field notebooks.

Reproduced with the permission of the Syndics of Cambridge University Library and William Huxley Darwin.


[illeg]by N N by E SE by S NE by E SE by E ++ NE by N ++
[illeg]by W NE by N NW + NE + SE by E + NE by N +
[illeg]E NE NW NE SW SE
[illeg]by E NE by W W N W by N + N by E + ([illeg] N.)
  N SE + NE + SW by W SE by S
  E     NW NE
      NW by W NE by N
  [illeg]first Fort Between do fort & light house.   Between lighthouse & N S. de Gracia  

[the left margin of the table is obscured by tape.]

Stratification very obscure, parts near town, like King Georges Sound mere waving lines; granite there siliceous. — where gneiss appears, sometimes even horizontal, in great circles: & irregularly yet upon the whole I really think a NE by N dip strike is just discernable. — dip oftener to SE than NW; angle [very] various. —

East Land a plain as seen from sea, peninsula but termination of chain of hills. water [soon] — flat valleys — little terrain in front of red clay — some ferruginous sandstones. — Conglomerates forming archways — Vast number of dikes. Many 3 & 4 yards wide close together — have aspect of true dike. parellel seams angular pieces of embedded granite. parallel dikes. — black very heavy Porphyry. minute crystal of glassy feldspar. many faults. — dike of this formation: one side as if fault, pieces removed, & [defressenated] within foot of space, in [flocculent] pieces in granite. Certainly appears as if granite has been melted — Mem last years section. — yet hard to believe not part of great neighbouring — stone of dike as at K. Georges Sound. Blueish grey compact gneiss, in parts silicious fine grained

V. specimen felspathic

[sketch to the right of this text]

A red granite

Dyke 45d wide

954 verso


seams highly micaceous. — quartzy veins, red-granite dike & masses, & irregular structure throughout gneiss. —

Parts of gneiss, globular structure like some trap rocks. — I saw the fissure with calcareous matter — a considerable quantity of chlorite

Tuesday 2d. [August 1836]

dip run
  W & E
NW by N NE by E
do do
N E & W
  NE by N
E by N N by W

From the Light house, proceeding East, then northwards: in whole way NW dip at all clear, certain generally a curvilinear structure, contorted, yet minerals always arranged in planes but not laminated rocks. — All that can be said is that the NE by N strike is not more infrequent than any other = In certain parts large crystals, or lumps of garnets see specimens. = Parts of globular granite, (compacted with the trap structure already mentioned). — honeycombed like sandstone. cylindrical vertical. rounded bottom; 2 or 3 diameters long, almost touching each other; from less than 1 & 1/2 inches to 3 inches diameter, full of water. = Country plain. Valleys as in Patagonia surface looks like red clay — on coast there is little curious — yet one mass quite soft. (see specimen) intersected granite like a dike. — (NB. Specimen of black angular fragments in dike granite), in some of decomposed granite. on plain small rounded quartzy pebbles. — a spherical decomposing structure visible = Plain slopes to seaward = Hard rock on coast entirely coated with marine bodies = the siliceous sandstone on the coast dips seaward. — separated by some yards of space from cliff of coast. forming low escarpment, is abundant, hard to tell which of these formations of to day & which yesterday. = Eschwege, Spix, & Smyth suggest be consulted. =

At a part of beach, — gneiss passing into greenstone coated, like varnish, most glassy, rich brown country: all rocks nearly a like; on each side & in bed of stream, small, muddy: only over rock in upper tidal limit gradually disappearing. above spring. — not on coast any other part or in stream. — [coating] on quartz pebbles (& on pebbles in crevices)

1 Eschwege 1832, Spix 1824, presumably Captain William Carmichael Smyth, R.N., whom Darwin mentioned as providing him with information in Coral reefs, p. 158. (JvW)


[Bonfin] — stratification very irregular, grouping of masses unintelligble — partly highly inclined, other sections of strata capping conformably irregularities, in truth probably subsidence. — Conglomerates very coarse, hard, next in quantity to conglomerate. a fine grained slaty dark [illeg] grey sandstone passing in clay slate, which substance predominate parts. — some of the sandstone strata hard & grey. — Parts of the masses micaceous — thickest part about 40 ft: — shales pale grey to dark blue, even black; only remarkable circumstance irregular cut masses (some yards across) others small of about angular shapes, hard grey non: calc: sandstone (embedded the more aluminous & darker coloured varieties) surface rough covered with minute point & lines. — concretions pass into strata. — These sandstones contain the F.O. shells. — specimens (          ). All the Helix-like shells found in the spot, the elongated kind most common. — considerably blow below high water mark (with Balanidae adhering to F.W. shells & dipping seaward. — covered by 40 ft. — subsidence [one word obscured by tape] on hole of 50 ft deep. occupied by fresh water. — (no Earthquakes). I think [illeg] then became perhaps grouped in families. I saw them only in these concretions —. NB Shell from & by [Bones] R. San. Francisco: Perhaps centre of Bonfin granitic axis. — No Barrier can be imagined to old Lake or old creek. — The connections with surfaces, apparently old seam, encrusted with distinct [2 words illeg]of Calc: Spar — N. B. I believe last year F.W. shells came from concretions, below merely to be reached at lowest water. — Because the wall seems to be basalt of such stone quarried from such situation. — In sandstone these veins & pisolitic balls of ferrug: sandstone [small sketch] vertical fissure & many home fissure secretion. —

955 verso


mahogany colouring in few parts blackish — stream with patches of ferrug: sandstone & conglomerate in bed. — all water is thus granitic land do = large fragment long ago broken off, perhaps for neighbouring old building, coated nearly as brightly — (see spec:), action of sea — polish resembling calc: rock at Ascension. — Mem. [moonrock] & Mica when stream rapid ?? — rock in sun & dry very pretty more so, than specimens show — a mere few yards in extent. = not effervesce, not stain Borax purple. —

NB The broard rectangular fissure in the modern sandstone rather singular. —

Sailed (6th) [August 1836]

Monday, Aug 1t [1836]. Entered, little disappointment, novelty & surprise gone, & circumstance not very favourable in evening took walk & Aug 2d do. — a great untidy hot house, smell, ornamented with houses & artificial gardens (well contrasted to wild luxuriance of houses nature) — [small sketch] Portugeese architecture. — hills & valleys — nature's menagerie for insects. — magnificent mango Jack Fruit & Orange, Cocoa Nut & Palm. — Splendid greens with bright sun — open epithet upon epithet. Botanic tell you name after name, & a short characteristic of each but that fail to all but the learned traveller. — distant low land across the bay. [Much] of [Boats] country itself a plain 2-300 ft [worn] by valleys (oh what delicious shady spots) but red hillocks [when some view] peep out. —
[sentence interlined]
& I stopped & stopped again to gaze on such beauty & to try to fix an impression which alas must die away merely leaving a Banana, a coco nut, [red] fruit trees, but the thousand beauties must perish in one's mind.

Fishing village; — grass hills — fine wild sea — Cocoa nuts — Number of blacks insurrection — women carrying heavy stones — almost wished for it. if without blood-shedding. Every lover of Nature, would do anything to see another planet, but the Tropics are other planet. — long city - churches convents, older & richer look than East coast of America, a marked style of architecture. — long to live some time there to drink deeply of these charms. —

Wednesday [3 August 1836] Pic nic: — Thursday [4 August 1836]. Bonfin — Well wet through
vertical sun best tops of trees — greatest pleasure I ever enjoyed; alternate view, all beautiful, structure of country - elements of views — Palms — If England had possessed it. —

These passages form the basis for part of Darwin's discussion in the Beagle diary, pp. 433ff. (JvW)


Examined the dikes. — The singular one with [small eject] of feld. & smal black, heavy base; is wonderfully crossed by faults & threads traverse whole neighboring gneiss. — I can just fancy water so injected. — rather different constitution from neighbouring grand dike — some of the faults appear as if intermediate space of red, hornblendic granite, [small sketch]

It is hard to set limits to injection of fluid rock — but certainly the threads & projecting points of Granite seem wonderfully blended together. Threads proceed from dikes, intersect some red granite. — & close by red granite [external] black angular pieces, which latter at least I think are embedded because cleavage seem rather to fold round them — Yet many of these angular pieces are deceptive, from oblique section irregular exposure of wall of irregular dike: — The number of great dikes considerable,

956 verso

decomposed granite capped with [illeg] bright red quartz clay, which generally is capped with few quartzy pebbles or rounded pieces of Granite — doubtful how far follow inequalities. — This covered by a pebbly earth. covering conforming to inequalities of country. — smooth — Mem creek Island along coast. — Some fine Porph. gneiss — 1/10

NB. The idea of ferruginous veins Bonfin being secretion will agree with their circular forms. — & concretionary process for causing a globular construction & hence do fissure

[in ink:] Bahia Brazil Aug: 1836

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