p 288
Among the general subjects of contemplation appertaining to a work of this
nature, a prominent place must be given, first, in the consideration of the
'quantity' of the land raised above the level of the sea, and next, to the
individual configuration of each part, either in relation to horizontal
extension (relations of form) or to vertical elevation (hypsometrical
relations of mountain-chains). Our planet has two envelopes, of which one,
which is general -- the atmosphere -- is composed of an elastic fluid, and
the other -- the sea -- is only locally distributed, surrounding, and
therefore modifying, the form of the land. These two envelopes of air and
sea constitute a natural whole, on which depend the difference of climate on
the earth's surface, according to the relative extension of the aqueous and
solid parts, the form and aspect of the land, and the direction and
elevation of mountain chains. A knowledge of the reciprocal action of air,
sea, and land teaches us that great meteorological phenomena can not be
comprehended when considered independently of geognostic relations.
Meteorology, as well as the geography of plants and animals, has only begun
to make actual progress since the mutual dependence of the phenomena to be
investigated has been fully recognized.
Pages:
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607