air: a candle cannot be lighted without their instantly flying upon it, and putting out the flame*. The closest recesses are no safeguard from their annoyance; and the most beautiful landscapes of nature only serve to invite their rapacity. As these are injurious from their multitudes; so most of the larger kinds are equally dreadful to him, from their courage and ferocity. In the most uncultivated parts of the forest these maintain an undisputed empire; and man invades their retreats with terror. These are dreadful; and there are still more which are utterly useless to him, that serve to take up the room which more beneficial creatures might possess; and incommode him, rather with their numbers than their enmities. Thus, in a catalogue of land-animals, that amounts to more than twenty thousand, we can scarcely reckon up an hundred that are any way useful to him; the rest, being either all his open, or his secret enemies, immediately attacking him in person, or intruding upon that food he has appropriated to himself. Vegetables, on the contrary, though existing in greater variety, are but few of them noxious. The most deadly poisons are often of great use in medicine; and even those plants that only seem to cumber the ground, serve for food to that race of animals which he has taken into friendship or protection. The smaller tribes of vegetables, in particular, are cultivated as contributing either to his necessities or amusement; so that vegetable life is as much promoted by hu

* Ulloa's Description of Guayaquil.

man industry, as animal life is controlled and diminished.

Hence, it was not without a long struggle and various combinations of experience and art, that man acquired his present dominion. Almost every good that he possesses was the result of the contest; for, every day, as he was contending, he was growing more wise; and patience and fortitude were the fruits of his industry.

Hence, also, we see the necessity of some animals living upon each other, to fill up the plan of Providence; and we may, consequently, infer the expediency of man's living upon all. Both animals and vegetables seem equally fitted to his appetites; and, were any religious, or moral motives, to restrain him from taking away life, upon any account, he would only thus give existence to a variety of beings made to prey upon each other; and, instead of preventing, multiply mutual destruction.

CHAP. XXIV.

Of the Generation of Animals. BEFORE we survey animals in their state of maturity, and performing the functions adapted to their respective natures, method requires that we should consider them in the more early periods of their existence. There has been a time when the proudest and the noblest animal was a partaker of the same imbecility with the meanest reptile; and, while yet a candidate for existence, equally help

less and contemptible. In their incipient state all are upon a footing; the insect and the philosopher being equally insensible, clogged with matter, and unconscious of existence. Where then are we to begin with the history of those beings, that make such a distinguished figure in the creation? Or, where lie those peculiar characters in the parts that go to make up animated nature, that mark one animal as destined to creep in the dust, and another to glitter on the throne?

This has been a subject that has employed the curiosity of all ages, and the philosophers of every age have attempted the solution. In tracing Nature to her most hidden recesses, she becomes too minute or obscure for our inspection; so that we find it impossible to mark her first differences, to discover the point where animal life begins, or the cause that conduces to set it in motion. We know little more than that the greatest number of animals require the concurrence of a male and female to re-produce their kind; and that these, distinctly and invariably, are found to beget creatures of their own species. Curiosity has, therefore, been active, in trying to discover the immediate result of this union, how far either sex contributes to the bestowing animal life, and whether it be to the male or female that we are most indebted for the privilege of our existence,

Hippocrates has supposed that fecundity proceeded from the mixture of the seminal liquor of both sexes, each of which equally contributes to the formation of the incipient animal. Aristotle, on the other hand, would have the seminal liquor in the male alone to contribute to this purpose,

while the female supplied the proper nourishment for its support. Such were the opinions of these fathers of philosophy; and these continued to be adopted by the naturalists and school-men of succeeding ages, with blind veneration. At length, Steno and Harvey, taking anatomy for their guide, gave mankind a nearer view of nature, just advancing into animation. These perceived in all such animals as produced their young alive, twoglandular bodies, near the womb, resembling that ovary, or cluster of small eggs, which is found in fowls; and, from the analogy between both, they gave these also the name of ovaria. These, as they resembled eggs, they naturally concluded had the same offices; and, therefore, they were induced to think that all animals, of what kind soever, were produced from eggs. At first, however, there was some altercations raised against this system; for, as these ovaria were separate from the womb, it was objected that they could not be any way instrumental in replenishing that organ, with which they did not communicate. But, upon more minute inspection, Fallopius, the anatomist, perceived two tubular vessels depending from the womb, which, like the horns of a snail, had a power of erecting themselves, of embracing the ovaria, and of receiving the eggs, in order to be fecundated by the seminal liquor. This discovery seemed, for a long time after, to fix the opinions of philosophers. The doctrine of Hippocrates was re-established, and the chief business of generation was ascribed to the female. This was, for a long time, the established opinion of the schools; but Leuwenhoeck, once more, shook the whole system,

and produced a new schism among the lovers of speculation. Upon examining the seminal liquor of a great variety of male animals, with microscopes, which helped his sight more than that of any of his successors, he perceived therein infinite numbers of little living creatures, like tadpoles, very brisk, and floating in the fluid, with a seeming voluntary motion. Each of these, therefore, was thought to be the rudiments of an animal, similar to that from which it was produced; and this only required a reception from the female, together with proper nourishment, to complete its growth. The business of generation was now, therefore, given back to the male a second time, by many; while others suspended their assent, and chose rather to confess ignorance than to embrace error*.

In this manner has the dispute continued for several ages, some accidental discovery serving, at intervals, to renew the debate, and revive curiosity, It was a subject where speculation could find much room to display itself; and Mr. Buffon, who loved to speculate, would not omit such an opportunity of giving scope to his propensity. According to this most pleasing of all naturalists, the microscope discovers that the seminal liquor, not only of males, but of females, also, abounds in these moving little animals, which have been mentioned above, and that they appear equally brisk in either fluid. These he takes not to be real animals, but organical particles, which, being simple, cannot be said to be organised themselves, but go to the composition of

* Bonet Considerations sur les Corps Organisés.