CHAPTER XIV.

PROSPECTIVE CONTRIVANCES.

I CAN hardly imagine to myself a more diftinguishing mark, and, consequently, a more certain proof of defign, than preparation, i. e. the providing of things beforehand, which are not to be used until a confiderable time afterwards; for this implies a contemplation of the future, which belongs only to intelligence.

Of these prospective contrivances the bodies of animals furnish various examples.

I. The human teeth afford an inftance, not only of profpective contrivance, but of the completion of the contrivance being defignedly fufpended. They are formed within the gums, and there they ftop: the fact being, that their further advance to maturity would not only be useless to the new-born animal, but extremely in its way; as it is evident that the act of fucking, by which it is for fome time to be nourished, will be performed with more ease both to the nurse and to the

infant, whilst the infide of the mouth, and edges of the gums, are fmooth and soft, than if fet with hard pointed bones. By the time they are wanted, the teeth are ready. They have been lodged within the gums for fome months paft, but detained, as it were, in their fockets, fo long as their further protrufion would interfere with the office to which the mouth is deftined. Nature, namely, that intelligence which was employed in creation, looked beyond the first year of the infant's life; yet, whilft she was providing for functions which were after that term to become neceffary, was careful not to incommode those which preceded them. What renders it more proba ble that this is the effect of design is, that the teeth are imperfect, whilst all other parts of the mouth are perfect. The lips are perfect, the tongue is perfect; the cheeks, the jaws, the palate, the pharynx, the larynx, are all perfect. The teeth alone are not fo. This is the fact with respect to the human mouth; the fact alfo is, that the parts above enumerated, are called into ufe from the beginning; whereas the teeth would be only fo many obstacles and annoyances, if they were there. When a

contrary order is neceflary, a contrary or der prevails. In the worm of the beetle, as hatched from the egg, the teeth are the first things which arrive at perfection. The infect begins to gnaw as foon as it escapes from the shell, though its other parts be only gradually advancing to their maturity.

What has been obferved of the teeth, is true of the borns of animals; and for the fame reafon. The horn of a calf or lamb does not bud, or at least does not sprout to any confiderable length, until the animal be capable of browfing upon its pafture; becaufe fuch a fubftance upon the forehead of the young animal, would very much-incommode the teat of the dam in the office of giving fuck.

But in the cafe of the teeth, of the human teeth at least, the profpective contrivance looks ftill further. A fucceffion of A fucceffion of crops is provided, and provided from the beginning; a fecond tier being originally formed beneath the firft, which do not come into use till feveral years afterwards. And this double or fuppletory provifion meets a difficulty in the mechanism of the mouth, which would have

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appeared almost unfurmountable. pansion of the jaw (the confequence of the proportionable growth of the animal, and of its skull,) neceffarily feparates the teeth of the first set, however compactly difposed, to à diftance from one another, which would be very inconvenient. In due time therefore, i. e. when the jaw has attained a great part of its dimenfions, a new fet of teeth fprings up, (loofening and pushing out the old ones before them) more exacly fitted to the space which they are to occupy, and rising also in fuch clofe ranks, as to allow for any extenfion of line which the fubfequent enlargement of the head may occafion.

II. It is not very eafy to conceive a more evidently profpective contrivance, than that which, in all viviparous animals, is found in the milk of the female parent. At the moment the young animal enters the world, there is its maintenance ready for it. The particulars to be remarked in this oeconomy are neither few nor flight. We have, firft, the nutritious quality of the fluid, unlike, in this respect, every other excretion of the body; and in which nature hitherto remains unimitated, neither cookery

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cookery nor chymiftry having been able to make milk out of grafs: we have, fecondly, the organ for its reception and retention: we have, thirdly, the excretory duct, annexed to it and we have, laftly, the determination of the milk to the breaft, at the particular juncture when it is about to be wanted. We have all these properties in the fubject before us; and they are all indications of defign. The last circumftance is the ftrongest of any. If I had been to guess beforehand, I should have conjectured, that, at the time when there was an extraordinary demand of nourishment in one part of the fyftem, there would be the leaft likelihood of a redundancy to fupply another part. The advanced pregnancy of the female has no intelligible tendency to fill the breasts with milk. The lacteal fyftem is a conftant wonder: and it adds to other caufes of our admiration, that the number of the teats or paps in each fpecies is found to bear a proportion to the number of the young. In the fow, the bitch, the rabbit, the cat, the rat, which have numerous litters, the paps are numerous and are difpofed along the whole length of the belly:

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