OCR Text |
Show 454 GALAPAGOS ARCHIPELAGO. Sept. 1835. circumstance which, perhaps, is chiefly owing to the singularly low temperature of the surrounding sea. Excepting during one short season, very little rain falls, and even then it is not regular: but the clouds generally hang low. From these circumstances the lower parts of the islands are extremely arid, whilst the summits, at an elevation of a thousand feet or more, possess a tolerably luxuriant vegetation. This is especially the case on the windward side, which first receives and condenses the moisture from the atmosphere. In the morning (17th,) we landed on Chatham Island, which, like the others, rises with a tame and rounded outline,. interrupted only here and there by scattered hillocks-the remains of former craters. Nothing could be less inviting than the first appearance. A broken field of black basaltic lava is every where covered by astunted brushwood, which shows little signs of life. The dry and parched surface, having been hea_ted by the noonday sun, gave the air a close and sultry feeling, like that from a stove : we fancied even the bushes smelt unpleasantly. Although I diligently tried to collect as many plants as possible, I succeeded in getting only ten kinds; and such wretched-looking little weeds would have better become an arctic, than an equatorial Flora. The thin woods, which cover the lower parts of all the islands, excepting where the lava has recently flowed, appear from a short distance quite leafless, like the deciduous trees of the northern hemisphere in winter. It was some time before I discovered, that not only almost every plant was in full leaf, but that the greater number were now in flower. Mter the period of heavy rains, the islands are said to appear for a short time partially green. The only other country, in which I have seen a vegetation with a character at all approaching to this, is at the volcanic island of Fernando Noronha, placed in many respects under similar conditions. The natural history of this archipelago is very remarkable: it seems to be a little world within itself; the greater number of its inhabitants, both vegetable and animal, being found Sept. 1835. VOLCANOES. 455 nowhere else. As I shall ~efer to this subject again, I will only. here remark, as formmg a striking character on first landing, t~at the birds are strangers to man. So tame and unsuspectmg were they, that they did not even understand what was meant by stones being thrown at them ; and quite re?ardless of us, they approached so close that any number might have been killed with a stick. The Beagle sailed round Chatham Island, and anchored in ~everal bays. One night I slept on shore, on a part of the Island where some black. cones-the former chimneys of the subterranean heated . flmds-were extraordinarily numerous. From one small emmence, I counted sixty of these truncated hillocks, which were all surmounted by a more or less pe~fect crater. The greater number consisted merely of a r~ng of red scorire, or slags, cemented together : and their hmght above the plain of lava, was not more than from fifty to a hundred feet. From their regular form, they gave the country a w01·kshop appearance, which strono-]y reminded me of those parts of Staffordshire where the 0g~eat iron-foundries are most numerous. The age of the various beds of lava was distinctly marked by th~ comparative growth, or entire absence, of vegetation. N othmg can be imagined more rough . and horrid than the surface of the more modern streams. These have been aptly compared to the sea petrified in its most boisterous moments : no sea, however, would present such irregular undulations, or would be traversed by such deep chasms. All the craters are in an extinct condition; and although the age of the different streams of lava could be so clearly distinguished, it is probable they have remained so for many centuries. ,.fhere ~s no account in any of the old voyagers of any volcano on this Island .having been seen in activity; yet since the time of Dampier {1684), there must have been some increase in the quantity of vegetation, otherwise so accurate a person would not have expressed himself thus :- "Four or five of the easternmost islands are rocky, barren, and hiJly, producing neither |