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This small Island lies in 0.58' N. & 29° 15' West longitude. The total circumference is barely 3/4 of a miles, the highest eminence about 50 feet above the sea. — It may be considered as the peak of a submarine mountain. At 1/4 of a mile distance, no bottom could be found, excepting on the West, where it shelved a little. Apparently in most places the sides are perpendicular beneath the sea. — The rocks are serpentine. & in the lower parts mixed with much Diallage. — the whole island is intersected with veins or beds of various substances. 235...239 — The serpentine. contain Feldspar, Chlorite & traces of Copper. — The diallage 242...245, contains bronzite. Feldspar. Mica Serpentine & Chlorite. — This rock weathers in a curious manner. owing to the washing away of minute veins of Serpentine. —

The third rock 240 & 241 is much veined with serpentine I am ignorant of its nature. The veins or beds are of three sorts. — One 252-253 of a decomposing vesicular mineral. infusible not effervescing with Acids: 2^d a conglomerate of Diallage. with a matrix of the same. — does not effervesce. with acids. — 246-248 this ought rather to be considered as a bed (?) instead of vein: it dips to the S. & was only place where I could see anything like stratification. —

3^d sort is a conglomerate of diallage &

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(a) the action of the weather has a curious effect on the serpentine rock. the outside in many places with a white mineral with an unctuous feel. — This cause give the island at a short distance a very white appearance. — which has by navigators been solely attributed to birds dung. —

(b) The perpendicular face of the rock although exposed to the full force of the Atlantic. swell which even on the calmer days is considerable, is yet matted with Fuci Zoophite & shells. — Is not this a strong proof t what little power pure water by itself has of wearing away the surfaces of rocks. Vide "Cuviers theory of earth"¹ on this subject

¹ Cuvier 1817.

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Feldspar in a hard calcareous base. — Perhaps this latter one may be of a different origin from the other two. 249..251 — The latter former ones from their numbers & the manner, in which they are interlaced I should think were formed at the same time as the rock.

The Serpentine or cleavage Diallage (a) is much divided by cleavage. which is in a perpendicular direction. — The Island. in works of navigation has wrongly been described as consisting of several distinct rocks. — It is nearly circular with a large oval opening in centre through which the sea flows. — There are a few small outlying rocks. —

This little speck in the Atlantic (b) is 350 miles from the nearest land, which is the island Fernando Noronha. & 540 from the coast of S America. —

I will here add the few other observations I made. — The island is entirely destitute of vegetation: it affords a secure a building place for countless numbers of boobys & noddys: They hitherto have had so little cause to dread man, that we killed numbers with my geological hammer. — The Boobys lay their eggs on the bare ground; the noddys make a sort of orpi nest with sea-weed. — By the side of the female noddy on the nest, there generally was lying a small flying fish. It was very amusing to see the large crabs with which the rock is covered, quietly

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stealing them. — The only other inhabitants were numbers of [Flies] & Ornithomya. the latter on the bodies of the Boobys. — I think it is a new species. — There were several spiders. A Staphylinus in the dung. & a small brown moth. — What this latter isolated little being found to live-on I am quite at a loss even to guess. — I believe what I have mentioned is the whole Fauna of the Island of St Pauls. — Whilst I we were busy in collecting the birds & their eggs. the men in boats caught numbers of fine fish. & had it not been for the vast numbers of sharks they would have soon filled the boat. —

Is not this the first Island in the Atlantic which has been shown not to be of Volcanic origin? —