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through which it ought to be moving forward. The way of preventing a reflux of the fluid, in both these cases, is to fix valves, which like flood gates, may open, a way to the stream in one direction, and shut up the passage against it in another. The heart, constituted as it is, can no more work without valves, than a pump can. Valves, therefore, properly disposed, are accordingly provided. A valve is placed in the communication between each auricle and its ventricle, lest, when the ventricle contracts, part of the blood should get back again into the auricle, instead of the whole entering, as it ought to do, the mouth of the artery. A valve is also fixed at the mouth of each of the great arteries which take the blood from the heart, leaving the passage free, so long as the blood holds its proper course forward ; closing it whenever the blood, in consequence of the relaxation of the ventricle, would attempt to flow back.'

But we must close this long quotation, and which will be best done in the words of this celebrated philosopher, who observes, ' The wisdom of the Creator,' saith Hamburgher, ' is in nothing seen more gloriously than in the heart.' And how well doth it execute its office! An anatomist who understood the structure of the heart, might say beforehand, that it will play; but he would expect, I think, from the complexity of its mechanism, and the delicacy of many of its parts, that it should always be liable to derangement, or that it would soon work itself out. Yet shall this wonderful machine go, night and day, for eighty years together, at the rate of a hundred thousand strokes every twenty-four hours, having, at every stroke, a great resistance to overcome; and shall continue this action, for this length of time, without disorder, and without weariness.' Well might the psalmist say, "Neither are there any works like unto thy works.'

Its great excellence and suitableness to the subject before us, induces me to venture on one more short paragraph from the same author. There are' he obseryes, brought together within

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the cavity of the mouth, more distinct uses, and parts executing more distinct offices, than, I think, can be found lying so near to one another, or within the same compass, in any other portion of the body ; viz. teeth of a different shape, first for cutting, secondly for grinding, muscles, most artificially disposed for carrying on the compound motion of the lower jaw; half lateral and half vertical, by which the mill is worked; fountains of saliva, springing up in different parts of the cavity for the moistening of the food, whilst the mastication is going on; glands, to feed the fountains , a muscular construction of a very peculiar kind, in the back part of the cavity, for the guiding of the prepared aliment into its passage towards the stomach, and in many cases for carrying it along that passage.

Now let any person consider what is here advanced, together with what has been said on the circulation of the blood, on muscular motion, and the adaptation of the members of the body to perform their several offices; in other words, review what has been advanced on the human frame, and then ask whether our proposition respecting it is not demonstrated; viz. that it abounds with the clearest indications of being, not the work of chance, but the work of an infinitely intelligent and almighty Creator.

So far, therefore, as the necessity for farther proof is concerned, it might seem superfluous here to add more. however, for the sake of the younger members of families whom I shall be happy to interest and profit, briefly advert to the structure of the human eye, being persuaded that it unites with the organs of speech to proclaim The hand that made us is divine.' For, says a learned man, of the eye, 'This member of animal bodies is of a most marvellous construction. It consists of six different coats, between which are placed a watery, crystalline, and glassy humour. Its vessels are nerves, glands, arteries, and veins. The whole is disposed, that the rays of light, and objects represented thereby, may be collected at the bottom of the eye.' -The author who has already so largely contributed to our en

I will,

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tertainment and instruction, speaking of the eye, and comparing it with the telescope, remarks ;– As far as the examination of the instrument goes, there is precisely the same proof that the eye was made for vision, as there is that the telescope was made for assisting it. They are made upon the same principles, both being adjusted to the laws by which the transmission and refraction of rays of light are regulated.'

Again

"The chamber of the eye is a camera obscura, which, when the light is too small, can enlarge its opening ; when too strong, can again contract it ; and that without any other assistance than that of its own exquisite machinery. It is further also, in the human subject, to be observed, that this hole in the eye which we call the pupil, under all its different dimensions, retains its exact circular shape. This is a structure extremely artificial.— Let an artist only try to execute the same. He will find that his threads and strings must be disposed with great consideration and contrivance, to make a circle, which shall continually change its diameter, yet preserve its form. This is done in the eye by an application of fibres, i. e. of strings, similar, in their position and action, to what an artist would and must employ, if he had the same piece of workmanship to perform.' • Observe a new born child', continues our author, ' first lifting up its eyelids. What does the opening of the curtain discover ? The anterior part of two pellucid globes, which when examined, are found to be constructed upon strict optical principles; the self-same principles upon which we ourselves construct optical instruments.'

But having, I fear, already much exceeded the bounds of propriety in these quotations, we must take our leave of this part of our subject.

TANT

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