8 ST. PAUL'S ROCKS chap. 



gained a deeper part, it darted away, leaving- a dusky train of 

 ink to hide the hole into which it had crawled. 



While looking for marine animals, with my head about two 

 feet above the rocky shore, I was more than once saluted by a 

 jet of water, accompanied by a slight grating noise. At first I 

 could not think what it was, but afterwards I found out that it 

 was this cuttle-fish, which, though concealed in a hole, thus 

 often led me to its discovery. That it possesses the power of 

 ejecting water there is no doubt, and it appeared to me that it 

 could certainly take good aim by directing the tube or siphon 

 on the under side of its body. From the difficulty which these 

 animals have in carrying their heads, they cannot crawl with 

 ease when placed on the ground. I observed that one which I 

 kept in the cabin was slightly phosphorescent in the dark. 



St. Paul's Rocks. — In crossing the Atlantic we hove- to, 

 during the morning of February i6th, close to the island of St. 

 Paul's. This cluster of rocks is situated in o° 5 8' north latitude, 

 and 29° 15' west longitude. It is 540 miles distant from the 

 coast of America, and 350 from the island of Fernando 

 Noronha. The highest point is only fifty feet above the level 

 of the sea, and the entire circumference is under three-quarters 

 of a mile. This small point rises abruptly out of the depths of 

 the ocean. Its mineralogical constitution is not simple ; in 

 some parts the rock is of a cherty, in others of a felspathic 

 nature, including thin veins of serpentine. It is a remarkable 

 fact that all the many small islands, lying far from any con- 

 tinent, in the Pacific, Indian, and Atlantic Oceans, with the 

 exception of the Seychelles and this little point of rock, are, I 

 believe, composed either of coral or of erupted matter. The 

 volcanic nature of these oceanic islands is evidently an extension 

 of that law, and the effect of those same causes, whether 

 chemical or mechanical, from which it results that a vast 

 majority of the volcanoes now in action stand either near sea- 

 coasts or as islands in the midst of the sea. 



The rocks of St. Paul appear from a distance of a brilliantly 

 white colour. This is partly owing to the dung of a vast 

 multitude of seafowl, and partly to a coating of a hard glossy 

 substance with a pearly lustre, which is intimately united to the 

 -surface of the rocks. This, when examined with a lenSj is 



