see it; secondly, that the still fluid lava withinwas packed by the centrifugal force generated by the revolving ofthe bomb, against the external cooled crust, and so produced thesolid shell of stone; and lastly, that the centrifugal force, byrelieving the pressure in the more central parts of the bomb,allowed the heated vapours to expand their cells, thus forming thecoarse cellular mass of the centre. Structure of the land. The yawl at this place was anchored some way from the shore, and wehad fears for her safety from robbers during the night. The metalhad been fused, and although the room was about fifteen feet high,the globules, dropping on the chairs and furniture, had drilled inthem a chain of minute holes. Against so strong a current it was, of course, quite impossible torow or sail: consequently the three boats were fastened togetherhead and stern, two hands left in each, and the rest came on shoreto track. Banks, in which the grandmothersand mothers of the present race played a part. AtSt. It is remarkable that in all the different kinds ofglowworms, shining elaters, and various marine animals (such as thecrustacea, medusae, nereidae, a coralline of the genus Clytia, andPyrosoma), which I have observed, the light has been of awell-marked green colour. In the first part of the road we passed throughleafless thickets, as in Chatham
Island. If the different islands have theirrepresentatives of Geospiza, it may help to explain the singularlylarge number of the species of this sub-group in this one smallarchipelago, and as a probable consequence of their numbers, theperfectly graduated series in the size of their beaks. I felt the force of theremark that man, at least savage man, with his reasoning powersonly partly developed, is the child of the tropics. The beak is flattened laterally, that is, in a plane at rightangles to that of a spoonbill or duck. At high water the wavesbreak over it; at low water its summit is left dry, and it mightthen be mistaken for a breakwater erected by Cyclopean workmen. These two species of Amblyrhynchus agree, as I have already stated,in their general structure, and in many of their habits. Theircolour was red or dull white. (12/1. Owen informs me that a part of the oesophagus is so constructedthat nothing much larger than a crowquill can be passed down. Near the ArroyoTapes I heard of a wood of palms; and one of these trees, ofconsiderable size, I saw near the Pan de Azucar, in latitude 35degrees. Absence of Trees. HELENA. LANDING AT BUENOS AYRES. BERKELEY SOUND, FALKLAND ISLANDS. The weather continued very bad, but it at last permitted us
You've reached the end of your free preview.
Want to read all 3 pages?
- Spring '18
- Centrifugal Force, Pacific Ocean