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 teat, and is there fed with plenty. What makes it evidently appear that there is nothing in this fortuitous, but the work of a wise and foreseeing nature, is, that those females which bring forth many young, as sows and bitches, have many teats, and those which bear a small number have but few. What tenderness do beasts show in preserving and raising up their young till they are able to defend themselves! They say, indeed, that fish, when they have spawned, leave their eggs; but the water easily supports them, and produces the young fry in abundance. LII. It is said, likewise, that tortoises and crocodiles, when they have laid their eggs on the land, only cover them with earth, and then leave them, so that their young are hatched and brought up without assistance; but fowls and other birds seek for quiet places to lay in, where they build their nests in the softest manner, for the surest preservation of their eggs; which, when they have hatched, they defend from the cold by the warmth of their wings, or screen them from the sultry heat of the sun. When their young begin to be able to use their wings, they at tend and instruct them; and then their cares are at an end. Human art and industry are indeed necessary towards the preservation and improvement of certain animals and vegetables; for there are several of both kinds which would perish without that assistance. There are likewise innumerable facilities (being different in different places) supplied to man to aid him in his civilization, and in procuring abundantly what he requires. The Nile waters Egypt, and after having overflowed and covered it the whole summer, it retires, and leaves the fields softened and manured for the reception of seed. The Euphrates fertilizes Mesopotamia, into which, as we may say, it carries yearly new fields. The Indus, which is the largest of all rivers, not only improves and cultivates the ground,