mena. In the inferior orders of animals, a whole limb, or even the whole head, will be reproduced. This I have frequently witnessed. After decapitating a great number of snails, their heads were reproduced before the end of three months from the time it was done. By dividing earth-worms, also, I found that every piece produced a perfect worm, in a few weeks. The polypus may be divided into dozens of pieces, and every piece will become a perfect animal. Do not the results of these experiments clearly prove, that life is a general thing, capable of being divided and multiplied, reduced and increased, precisely in the same manner as any other species of matter? If life were an unity in every individual body, how could one body be multiplied into two bodies, and each of these become as perfect as the original? This phenomena of reproduction is very manifest in vegetables also, for a tree may be multiplied into a great number of trees, by slips being inserted into the ground. Can we shut our eyes against those striking phenomena, and cry out that life is something which we do not understand, and that it is not governed by the laws of matter? It is true, as has been already said, that we do not understand what the essence of life is; but, I would ask, do we know what the essence of any kind of matter is? Our knowledge consists in comparing dif ferent modifications of matter.

This phenomenon of design is evident during the whole life of bodies. When a body is perfect, nothing but growth and nutrition, with other necessary phenomena attending them, go forward; but, as soon as a member, or any other part of the body, is removed, another member, or part, of the same kind as the original, is produced in its stead; nay, in some cases, as when polypi, leeches, earth-worms, &c. are divided, Nature, through the agency of the vital principle, finds it easier, or more conducive to her purposes, to multiply an animal, or vegetable, into numerous bodies of a similar kind, than merely to endow the original body with its former perfection.

This power of reproduction is not nearly so strong in the higher order of animals as in the lower. In the former, a whole limb, or a whole bone, &c. will not be reproduced, but a part of a bone, muscle, &c. A number of proofs of this kind might be brought forward to show that a principle exists in the bodies of animals, and vegetables, which is the cause of their organic movements; and that this principle preserves the entity, and identity, of such bodies;-it feels their want, and supplies them ;-it regulates their organic motions ;-it gradually becomes diminished, and they decay. In infancy, it is small in quantity, but concentrated and vigorous: it, at this

time, has a strong affinity for tangible matter, which it assimilates into bodily structure: during manhood, its affinity for the tangible parts is not so powerful, and its quantity be comes diminished, and, perhaps, its quality changed towards the advancement of years.

A question will here naturally arise,-If the vital principle preserves the body, what is that preserves the vital principle? This question involves much consideration: it must be answered by comparison. The existence and phenomena of tangible matter are proved by their relation with the senses. The existence of the vital principle is proved by induction, from a consideration of its phenomena. The phenomena are proved by their relation with the senses. We know that matter exists, but we do not know how it came to exist. We know also that life exists, but we do not know how it came to exist. As we do not know the cause of either, further than that they indicate Power, Wisdom, Intelligence, Foreknowledge, &c., we conclude that both, and every thing, were produced by the same cause. Admitting, therefore, that life came into existence by the same power as other modifications of matter, we proceed to show how its identity may be preserved,-- how it may be propagated and multiplied,—how it may form the different modifications of structure.

We find that some parts of the body are formed of skin, some of flesh, some of brain and nerves, some of bloodvessels, some of gristle, some of different kinds of membranes, some of bone: there is liver in one part, heart in another, lungs in another, &c. This may be accounted for by admitting that the vital principle is differently modified in these parts. As the vital principle is the cause of the structure, the structure must be modified according to the modification of the vital principle; for instance, one portion of the vital principle is modified to form bone, another to form brain, another to form liver, &c. In vegetables, one portion is modified to form bark, another to form the woody fibres, another to form pith, &c. The life of one animal must be modified differently from that of another; and the life of vegetables from that of animals, &c. If this were not the case, and if the vital principle did not possess the power of preserving its own identity, and, consequently, preserving the identity of the body, men might become snails, horses might become flies, and sheep might become mulberry-trees: but the life of the body is modified, so as to preserve the identity, &c. of that body. This modification depends upon its elementary constitution; and the nature, or elementary constitution, of every individual life, was, probably, determined at the time of

creation.

It follows, from the above remarks, that no change can

take place in the structure, without a change first in the vital principle; but, if the vital principle becomes changed in its condition, the structure also will become changed. The vital principle may become, in a degree, changed in its condition by several external causes; the chief of which are air, food, and climate. This change constitutes predisposition, either to disease or to health, or, lastly, to any modification of the structure. As the life of one seat may have a nearer relation with any of these causes than that of another, especially if the cause is powerful, the bodily form may become in a degree altered. A successive application of the same causes, through several generations, may produce an evident alteration in the organization of animals. This phenomena is sufficiently obvious in both animals and plants: they alter their form according to the nature of the air, food, climate, &c. with which, and in which they live. This will be accounted for upon the principle that life is differently modified in every seat; and that each modification, in unison with the law of affinity, has a different relation with the external causes. This relation may tend either to increase, or diminish, the activity of the life of particular seats; or it may merely alter its condition, without altering the degree of its activity.

Nature is a circular chain of causes and effects. Causes join and produce effects; these effects again become causes for other effects; and this chain of causation is universal and constant. The atmosphere is universal, as it regards terrestrial beings; and it is a common support to them all. The life of one being, in a state of nature, does not depend upon another. The elements of the vital principle are common to all; they pervade the universe, and extend their influence over all animated Nature. Fire consumes the tangible parts of bodies, and converts their natural structure into another form; so does the vital principle consume the atmosphere, and become united with its vital elements: it converts the food to the nourishment of the body, and preserves itself from decay by its affinity for the elements of life, diffused throughout the

universe.

There are two supporters of life; these are air and food This may be proved both by analysis an have a relation with their effects, and independent of their causes. A mere a causation; for a succession of events any relation between these events. causation, we must prove successi of the cause in the effect, or a di cause and effect. This must1 analysis; for instance, I ma already in the room may

duced by the function of respiration. The vital elements are diffused by the blood, over every part of the body; and the vital principle, being active in these parts, converts it into a substance of its own nature. There is nothing uncommon in this process, as it has many analogies in nature. It is analogous to the action of fire on fuel, blood on chyle, acid on alkali; and, in fact, to all the phenomena in nature. It is governed by the laws of affinity, and attraction, in unison with the constant and undeviable process of causation. The vital elements, existing in the constitution of the atmosphere, are, doubtless, very differently modified from the vital principle, which is active in the body. It first undergoes a change by its union with the blood in the lungs of animals, and with the sap in the leaves of vegetables.

The atmosphere is a compound of many airs, and each of these produces its peculiar effect on the vital principle. That part of it, which we call oxygen, is the only one capable of supporting life. But oxygen and life are not identical. It evidently consists of, or contains the vital elements, and conse quently, bears a relation with life, by their having some properties in common. Oxygen has also properties in common with electricity, and caloric. When the oxygen inspired is increased, the functions of life are accelerated, which indicates an increase of vital principle. But this is no more proof that oxygen is life, than that fuel is fire. An increase of fuel will produce an increase of caloric; and an increase of oxygen will produce an increase of life. There is causation here, but no identity.

The elements of the vital principle have an affinity for each other, and also for the tangible parts of bodies. They unite with tangible parts, as caloric, or the electric matter, unites with different substances. Life is differently modified in every part and tissue of the body. In bone, it forms bony matter; in muscles, it forms flesh; in the skin, it forms skin, &c. This is owing to that portion of life which resides in bone, having an affinity for such materials only as will form bone; and so on, in every other part and tissue throughout the body. According to this law, every part will always be preserved in the same state, unless the condition of the vital principle be changed. Physical man will never change into physical brute; nor physical brute into vegetable. As long as the life is the same, the body must be the same, inasmuch as the body is determined by its life.

From this view of the subject, it would appear that life and death are only comparative states. A body may possess much life, or little life, or none at all. Its life may become modified in its condition, from a modification in the condition of