« VorigeDoorgaan »
contrary order is necessary, a contrary order prevails. In the worm of the beetle, as hatched from the egg, the teeth are the first things which arrive at perfection. The insect begins to gnaw as soon as it escapes from the shell, though its other parts be only gradually advancing to their maturity.
What has been observed of the teeth, is true of the horns of animals; and for the fame reason. The horn of a calf or lamb does not bud, or at least does not sprout to any considerable length, until the animal be capable of browsing upon its pasture; because such a substance upon the forehead of the young animal, would very much incommode the teat of the dam in the office of giving suck.
But in the case of the teeth, of the human teeth at least, the prospective contrivance looks still further. A succession of crops is provided, and provided from the beginning; a second tier being originally formed beneath the first, which do not come into use till several years asterwards. And this double or suppletory provision meets a difficulty in the mechanism of the mouth, which woidd have
appeared appeared almost unsurmountable. The expansion of the jaw (the consequence of the proportionable growth of the animal, and of its skull,) necessarily separates the teeth of the first set, hbwever compactly disposed, to k distance from one another, which would be very inconvenient. In due time therefore, i. e. when the jaw has attained a great part of its dimensions, a new set of teeth springs up, (loosening and pushing out the old ones before them) more exactly fitted to the space which they are to occupy, and rising also in such close ranks, as to allow for any extension of line which the subsequent enlargement of the head may occasion.
IL It is not very easy to conceive a more evidently prospective 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 economy are neither few nor slight. We have, first, the nutritious quality of the fluid, unlike, in this respect, every other excretion of the body; and in which nature hitherto remains ummitated, neither view v,. T 1 cookery
cookery nor chymistry having been able to make milk out of grass: we have, secondly, the. organ for its reception and retention: we have, thirdly, the excretory duct, annexed to it: and we have, lastly, the determination of the milk to the breast, at the particular juncture when it is about to be wanted. We have all these properties in the subject before us; and they are all indications ,of design. The last circumstance is the strongest 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 system, there would be the least likelihood of a redundancy to supply another part. The advanced pregnancy of the female has no intelligible tendency to fill the breasts with milk. The lacteal system is a constant wonder: and it adds to other causes of our admiration, that the number of the teats or pairs in each species is found to bear a proportion to the number of the young. In the sow, the bitch, the rabbit, the cat, the rat, which have numerous litters, the paps are numerous and are disposed along the whole length of the belly:
in the cow and mare they are few. The most simple account of this, is to refer it to a designing Creator.
But, in the argument before us, we are entitled to consider not only animal bodies when framed, but the circumstances under which they are framed. And, in this view of the subject, the constitution of many of their parts, is, most strictly, prospective.
III. The eye is of no use, at the time when it is formed. It is an optical instrument made in a dungeon; constructed for the refraction of light to a focus, and perfect for its purpose, before a ray of light has had access to it; geometrically adapted to the properties and action of an element, with which it has no communication. It is about indeed to enter into that communication; and this is precisely the thing which evidences intention. It is providing for the future in the closest sense which can be given to these terms; for it is providing for a future change: not for the then subsisting condition of the animal; not for any gradual progress or advance in that fame condition; but for a new state, the consequence of a great and sudden alteration, which the animal Is to undergo at its birth. Is it to be believed that the eye was formed, or, which is the fame thing, that the series of causes was fixed by which the eye is formed, without a view to this change; without a prospect of that condition, in which its fabric, of no use at present, is about to be of the greatest; without a consideration of the qualities of that element, hitherto entirely excluded, but with which it was hereafter to hold so intimate a relation? A young man makes a pair of spectacles for himself against he grows old: for which spectacles he has no want or use whatever at the time he makes them. Could this be done without knowing and considering the defect of vision to which advanced age is subject? Would not the precise suitableness of the instrument to its purpose, of the remedy to the defect, of the ednvex knse to the flattened eye, establish the certainty of the conclusion, that the case, afterwards to arise, had been considered beforehand, speculated upon, provided for? all which are exclusively the acts of a reasoning mind. The eye formed in one state, for use only in another state, and in a different state, affords a proof no less clear of destination te a suture purpose; and a proof pro