unsearchable to beings with our capacities. Every race of animals seems to have received from their Maker certain laws of extension at the time of their formation. Their elaborative organs were formed to produce this, while proper obstacles were opposed to its further progress. Below these limits they cannot fall, nor rise above them. What intermediate station they shall take may depend on soil, on climate, on food, on a careful choice of breeders. But all the manna of heaven would never raise the mouse to the bulk of the mammoth.
The opinion advanced by the Count de Buffon is, 1, That the animals, common both to the old and new world, are smaller in the latter. 2, That those peculiar to the new are on a smaller scale. 3, That those which have been domesticated in both, have degenerated in America; and, 4, That on the whole it exhibits fewer species. And the reason he thinks is, that the heats of America are less; that more waters are spread over its surface by Nature, and fewer of these drained off by the hand of man. In other words, that heat is friendly, and moisture adverse to the production and development of large quadrupeds. I will not meet this hypothesis on its first doubtful ground, whether the climate of America be comparatively more humid? Because we are not furnished with observations sufficient to decide this question. And though, till it be decided, we are as free to deny, as others are to affirm the fact, yet for a moment let it be supposed. The hypothesis, after this supposition, proceeds to another; that moisture is unfriendly to animal growth. The truth of this is inscrutable to us by reasonings a priori. Nature has hidden from us her modus agendi. Our only appeal on such questions is to experience; and I think that experience is against the supposition. It is by the assistance of heat and moisture
- Xviii. 100, 156. “La terre est demeurée froide, impuissante a produire les principes actife, a developer les germes des plus grands quadrupedes, auxquels il faut, pour croitre et se multiplier, toute la chaleur, toute l'activité que le soleil peut donner a la terre, amoureuse.”—Xviii. 156. “L'ardeur des hommes et la grandeur des animaux dependent de la salubrité et de la chaleur de l'air.—Ib. 160.