A manual of physiology : including physiological anatomy / by William B. Carpenter.
- William Benjamin Carpenter
- Date:
- 1856
Licence: Public Domain Mark
Credit: A manual of physiology : including physiological anatomy / by William B. Carpenter. Source: Wellcome Collection.
97/690 (page 65)
![I surface of the trees over which they cluster, a sufficiency of moisture I for their support, aud the parasitic species are replaced by others i which grow from fleshy roots implanted in the soil; but aged trunks i are now clothed with Mosses; decayed vegetables are covered with parasitical Fungi; and the waters abound with Confervse. In the warmer parts of the temperate regions, the Apricot, Citron, Orange, Lemon, Peach, Fig, Vine, Olive, and Pomegranate, the Myrtle, Cedar, Cypress, and Dwarf Palm, find their congenial abode. These ( give-place, as we pass northwards, to the Apple, the Plum, and the Cherry, the Chestnut, the Oak, the Elm, and the Beech. Groing further still, we find that the fruit-trees are unable to flourish, but the timber-trees maintain their ground. Where these last fai], i we meet with extensive forests of the various species of Firs; the [' Dwarf Birches and Willows replace the larger species of the same [ kind; and even near or within the arctic circle, we find wild flowers of great beauty,—the Mezereon, the yellow and white Water-Lily, and the Grlobe-flower. Where none of these can flourish, where trees wholly disappear, and scarcely any flowering-plants are to be I met-with, an humbler Cryptogamic vegetation still raises its head, in 1- proof that no part of the Grlobe is altogether unfit for the residence of living beings, and that the empire of Flora has no limit. 1 105. But distance from the Equator is by no means the only element in the determination of the mean temperature of a parti- cular spot, its height above the level of the sea being equally important; for this produces a variation in the amount of heat derived from the Sun, at least as great as that occasioned by difier- ence of latitude. Thus it is not alone on the summits of Hecla, Mount Blanc, and other mountains of arctic or temperate regions, that we find a coating of perpetual snow; we find a similar covering i on the lofty summits of the Himalayan chain, which extends to within a few degrees of the tropic of Cancer; and even on the higher peaks of that part of the ridge of the Andes which lies immediately beneath the Equator. The height of the S7iow-line beneath the j Equator is between 15,000 and 16,000 feet above the level of the , sea; on the south side of the Himalayan ridge, it is about 15,500 feet, but on the north side it rises to 18,500 feet; and in the Swiss Alps it is about 8000 feet. Its position is very much affected, I however, by local circumstances, such as the neighbourhood of a J) large expanse of land or of sea; hence the small quantity of land [ in the Southern hemisphere renders its climate generally so much colder than that of the Northern, that in Sandwich Land (which is i Lat. 59° S., or in the same parallel as the north of Scotland) the whole country, from the summits of the mountains down to the very brink of the sea-cliff's, is covered many fathoms thick with everlasting snow; and in the island of Georgia (which is in Lat. 54° S., or in the same parallel as Yorkshire), the limit of perpetual snow descends to the level of the ocean, the partial melting in](https://iiif.wellcomecollection.org/image/b20388160_0099.jp2/full/800%2C/0/default.jpg)
