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PHYSIOLOGY EVIDENCES DESIGN.

knows no change of character. How different are the terms in which the individual falling under physiological nature must be spoken of! Here the individuality lies in the peculiar aggregation of a great mass of different particles; no two individuals are exactly alike; no individual is exactly like itself even for a moment; there is a perpetual change; even the very atoms which compose the individual are continually disappearing the form remains, while the substance is continually changing; there is an unceasing rise, progress, decay, and dissolution; the dissolution, however, does not lie in the loss of the constituent substance, but in the failure of the indispensable form. Here, then, lies the great distinction between the individuals of physiological nature and the individuals of physical nature. In physical nature each individual retains throughout all time its proper identity; is always the same under the same circumstances; associates itself in innumerable ways with other individuals like itself, but never loses its own peculiar properties and character. The individual of physiological nature retains its identity through the best part of a century, while the substance which renders it a sensitive body is continually undergoing a change. It retains no identity of mere matter, but only an identity of form and spirit. An atom of carbon now exists in the crayon of the artist; now floats about the atmosphere from pole to pole in a new combination; now enters into the constitution of some vegetable nature; now is a component part of some animal frame; now is cast forth again into the atmosphere, and thus enjoys an immortality of existence altogether free from the laws of accident, disease, or death.

But

Physiology is the truest guide in medicine; and man is by nature a physician-is an observer of diseases, and of the means under which, whether by design or accident, diseases have disappeared. Medicine in its ruder states exhibits a few individuals who have not only been themselves diligent observers of diseases and remedies, but also inquirers into the experience of others. There are certain parts of medicine and surgery open to common observation without much risk of deception or error. as long as a man is ignorant of physiology he is groping in the dark; he is deceived at every step; he mistakes mere successive occurrences for events standing in the relation of cause and effect; and, if he be of a rash character, or even only of an ardent mind, he is very apt by his interference to aggravate rather than promote the cure of disease. When physiology has made some progress-that is to say, when the spirit in which the Creator willed the actions of living nature to take place has been apprehended—then men begin to discriminate the shades of disease with more accuracy, and to observe with less risk of error what remedies have contributed to a cure. Till physiology made such progress, medicine was overburdened with precepts rashly inferred by unskilful observers.

The last great use of the science of physiology to which we shall advert, is its intimate connection with that science which points out the evidence of design in nature; and it is in the organic world chiefly that we find such evidences.

It is a great error to suppose that human knowledge is confined to determining the laws according to which phenomena occur. Those who study the evidence of design in the universe, are sometimes reproached with deviating from the proper purpose of philosophy. They are told that philosophy has nothing to do with the origin of things; but only with the laws which regulate the phenomena which man is capable of observing. But this is an assumption purely gratuitous. It is quite true that man in early ages made small progress, attempting to find out the purpose for which everything that exists was made. It is also true that Bacon described final causes as barren of effect. But if we find that the knowledge of nature, and particularly of organic nature, has now advanced so far that the study of the purposes for which

INQUIRY NATURAL TO MAN.

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organic parts were made, leads to the elucidation of the science; and that the study of final causes is no longer that barren pursuit which it was in Bacon's time; then we are entitled to repel this reproach, and to consider on what grounds it is affirmed that man's knowledge must be confined within the investigation of the mere laws of phenomena, and not extend to the study of the purposes to which the various forms of organic structure are subservient. There is manifestly no other ground for affirming that human inquiry should be confined to the study of the laws according to which phenomena take place, than the argument that this is the only way in which human knowledge can be extended. Those who so argue altogether ignore physiology. The most ancient expression for physiology is the usus partium, that is to say, the use of the parts of the body. What does this mean? Surely it signifies that the study of the parts of the animal frame and of the vegetable structure, leads to a knowledge of the design with which the animal or the plant was made after that fashion. The discovery of the use of a part is not only a new step in physiology, but the observation of the relation between the structure of a part and its function is a fact in evidencing design. Till that discovery is made the human mind remains altogether unsatisfied with the most minute knowledge of the mere structure. The extent to which this is true will at once appear from the species of shame with which anatomists and physiologists point out those organs in the animal frame, the distinct use of which has not yet been discovered. There are such organs in the body, for example the spleen, the thyroid gland over the upper part of the windpipe, the supra-renal capsules, and some parts in the anatomy of the embryo. The most persevering efforts are continually made to connect the structure of such parts with some definite use in the living body. What are these efforts but the most conclusive confession that the human mind cannot rest satisfied with the mere knowledge of the size, the form, the minute internal structure of a part, unless it be able to conceive with what purpose that part was placed in the situation which it occupies?

The character of human knowledge is not to be sought in the speculations of philosophers. A far truer standard of the character of human knowledge will be obtained from the common principles which pervade the minds of mankind at large. It is vain to attempt to extinguish man's curiosity to know why a part was so constructed, or why it was placed in the situation which it occupies. Such inquiries are as natural to him as the desire to discover the laws which regulate the succession of phenomena. It is not to be supposed, however, that man has been gifted with powers sufficient to discover the whole plan on which organic nature is constructed. He need not expect to become able to explain the particular purpose of every variety of structure which he discovers in the animal and vegetable kingdom. It is long since physiology reached the truth that, in some species, there are parts of structure which do not seem to have any special office, or any special bearing on peculiar habits. It is long since physiology became acquainted with what are termed rudimentary structures, both in the imperfect and in the mature state of individuals. The simplest example of a rudimentary organ is the mamma in the male of the human race. It performs no office. The disciple of a positive philosophy points to those organs, and sneeringly asks how this is to be reconciled with our doctrines. But, suppose all the rudimentary organs which are known, and all the peculiarities of structure in animals, which seem to serve no useful purpose in relation to the habits of the animal, were deducted; what an infinitesimal proportion would the total amount of these make as compared with the vast array of organs with distinct uses, left to constitute the evidence of design! The disciple of a positive philosophy sarcastically asks, of what use it is

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PHYSIOLOGY A HYMN IN PRAISE OF GOD.

to the whale to have the bones corresponding to each of the bones in the human arm, or upper extremity? Here we answer by referring him to his favourite term, LAW: it is a law that the great orders of animals are developed upon one grand type. This law we discover by observation; it is a part of inductive science; it has nothing to do with design. But, having ascertained this law of development according to the type, we then discover that that type is made to bend into a conformity with the particular habits and usages of each species.

Here, then, is a great fact; and notwithstanding the law, in obedience to which the unwieldy whale, with its short fin-like arms, has in those arms a bone corresponding to every one of those in the human upper extremity, yet are these analogies of the human bones so modified as in the most perfect manner to become subservient to the different uses to which this animal applies its anterior extremity. The disciple of the positive philosophy no doubt says surely the fore-paw of a whale might have been constructed on a more simple plan, to answer all the uses to which it is subservient. But does this answer shake the foundations of the evidences of design? Before his arguments become of any avail, he must show that the fore-paw of the whale is unfit for the purposes required by the habits of that animal, because it is framed on the type of the human upper extremity. We do not pretend to say why it has pleased the AUTHOR OF NATURE to establish that law according to which the skeleton of mammals conforms to a certain type; but we do affirm that the AUTHOR OF NATURE, having restricted His creative power within the limits of that type, has displayed incontrovertible evidence of design in adapting the type of the human arm to the form of the fore-paw of the whale, in conformity with the uses which that part has to perform.

Such, then, is the kind of difficulty which presents itself in our reasonings upon design. The physiologist should never forget that his subject falls under the laws of inductive science, in as far as these are applicable to it; and he should never permit the disciple of a positive philosophy to refuse him the alternative of so regarding it, or considering the discovery of the fitness of means to an end as a new step in its progress.

A very remarkable feature in physiological nature is, that, after all, each individual, though composed of materials derived from mineral nature, is not dependent for his individuality and identity on the continued presence of that same aggregate of mineral substances. At every moment the materials of which a human being is composed are passing away, and giving place to new materials derived from without. In a short period of time, the substance of his body is entirely changed, yet his individuality, his identity, his personality remain. He is the same, and yet different. He is no longer the same matter; but he is the same man. The man is therefore something different from matter. Let the disciple of the positive philosophy expound this to us; if everything be material-if all the phenomena of the organic world be the result of internal laws belonging to material substances, what is it that represents man throughout his long life, notwithstanding the perpetual change of the matter which at any one moment composed his bodily frame? Man surely is something different from matter; he is a thinking spirit, and one of the earliest of his thoughts is to refer the changes which he sees taking place around him to Infinite Power, and to recognise in the accommodation of means to ends, the inherent design of Infinite Intelligence.

Truly did Galen say-"The study of physiology is a hymn in honour of the Deity."

THE EDITOR.

Before entering upon the disposition of the bony matter, a few words may be premised as to the composition of that matter in the different classes of Vertebrata. These classes are four :-Fishes, Reptiles, Birds, and Mammals, which latter class includes the hair-clad beasts, commonly called quadrupeds, with the naked whales and human kind. Fishes have the smallest proportion, birds the largest proportion, of the earthy matter in their bones. The animal part in all is chiefly a gelatinous substance.

PROPORTIONS OF EARTHY OR INORGANIC, AND OF ANIMAL OR ORGANIC, MATTER IN THE BONES OF THE VERTEBRATE ANIMALS.

From the above table it will be seen that the bones of the fresh-water fishes have more animal matter, and are, consequently, lighter than those of fishes from the denser element of sea-water; and that the marine mammal called porpoise differs little from the sea-fish in this respect. The batrachian frog has more animal matter in its bones than the ophidian or saurian reptiles, and thereby, as in other respects, more resembles the fish. Serpents almost equal birds in the great proportion of the osseous salts, and hence the density and ivory-like whiteness of their bones.

The chemical nature of the inorganic or hardening particles, and of the organic basis of bone, is exemplified in the subjoined Table, including a species of each of the four classes of Vertebrata :