themselves into the common receptacle to begin anew their alternating movement. Here we have a fluid which is manufactured within the animal system, and is the concentrated nourishment which is sent to every part to invigorate and increase the growth before maturity; to support the body when at its prime of strength; and to retard decay when the powers have begun to fail.

LIVING ORGANISMS EFFECT THEIR OWN PURIFICATION.

But this fluid itself must be purified from the excreta which it gathers as a scavanger-for it performs the double function of nurture and purification-in its passage through every nook and corner of the animal frame. It comes in contact with the air and moisture during its progress through the lungs, and thus keeps itself pure while cleansing the whole system which it supports. This admirable process of carrying life into every part by a circulating fluid in the case of the higher animals, blood; in the lower, especially in insect life, we may call it ichor, or any other name which seems to be appropriate, but is essentially the same -moves in like manner, and effects a corresponding purpose. This may be seen in the minutest organism which can be examined by the magnifying power of the glass to aid our organs of vision; and doubtless continues to the nth degree of smallness, being evidently a part of an organized system which ramifies all

nature.

The like offices for growth and support are accomplished in the same way substantially in the vegetable as in the animal kingdom, the differences being that there is no immediate reciprocal action within the system. For the nourishment drawn from without, after being once used, is given back to the source whence it was derived. There is a vascular system beginning in the remotest roots, continued through the trunk and branches, and ending with the twigs and leaves. The action is not through diverse channels emptying into each other, as the arteries and veins; but one system appears, by direct and reflex action, to perform the functions of both. For through foliage, which corresponds to the lungs in

the animal economy, the tree breathes and draws its nourishment from the nitrogen and oxygen of the atmosphere. This may be proved from the fact that growing crops are powerfully stimulated by feeding them with nitrogen, and that the water supply may be drawn from the air exclusively-not only to support life, though there be no water poured upon the roots, but, by the same means, the growth continued. For the leaves will drink in a moderate shower of rain and prevent it from reaching the earth and wetting the roots-as though the method of absorption through the leaves were the more direct way of appropriating moisture. In like manner the foliage respires as well as inspires, or breathes in-so that it becomes, just as in the method by lungs, an excretory process-in the case of vegetables the only way for the exercise of this function-to purify the system by casting out the residuum of food after absorbing the needed supply of nurture. This process of vascular circulation, of respiration and absorption, is, in the vegetable world, carried on in every organism; whether the oak of Bashan or the minutest growth that the microscope discloses. There is a completely organized system in each and every genus, as well as individual, differing in unessentials as to means and methods of their application, but achieving the same results.

RECIPROCAL ACTION IN LIVING ORGANISMS COPIED

IN MACHINERY.

The same power of duplication and correlative action, which man copies in the reverberating movement of his engines where is noticed the fundamental condition of all movement, i. e., that action and reaction must be equal-is here seen as in the unit of expulsion. Thus for the life movement, as the reverberation in circulation may be called, there is a corresponding adaptation of external nature to the processes of intellectual life. The latter may be called subjective, the former objective; and there is such a correlation between the two just as in the vascular system, that the one works into the others hands. The vascular system would be of no use were there not something either ready prepared, as

the air and water, for its appropriation, or of such a kind that the energies of the body can elaborate them, first by analysis and then by combination, so as to get the materials appropriate for nurture and growth.

NATURE, A CALCULUS OF DIFFERENTIATING AND INTEGRATING.

Thus, the highest processes of Nature are a never-ending employment of differentiating and integrating by which her modes of marking out her sublime results are the counterpart of the calculus in its dealing with pure quantity. For the differential calculus in separating factors into their minutest elements prepares the way for the integral to connect them again into the expression of whole numbers just as the process of growth completes its products.

There is the external or objective constitution of things corresponding precisely with the internal structure, so that there is reciprocal action as the order of nature; showing that the one thing is placed over against the other whereby both become component parts of one organism. Thus the ideal and the real are counterparts of nature organized into a system. They are the external and internal Replica of one organization; which, as a hemisphere, would be mutilated unless it existed double, and hence we have nature in its corresponding halves effecting a complete unity.

LIVING ORGANISM DEPENDENT UPON THE MUTUAL CoOPERATION OF THE SEVERAL PARTS.

But we have, if possible, a still more far-reaching and cogent proof of organized system in the reciprocal formation and function of the different parts in the living animal. There are in each animal the most diverse constituents. We have spoken of the blood as the means of disseminating nurture. There are the bones constituting the frame-work of the whole organism. There are the ligatures, or cords which hold these together. There are the processes and sockets by which movement in every direction is effected. Next, there are muscles with cord attachments at the ends and swelling out into masses in the middle for developing

ure.

and applying power. There is the flesh for giving roundness and beauty to the figure, with adipose as fuel to consume for heat, and as a repository of strength in case of failure through lack of food, when the system is able to use it; or a savings bank deposit on which to draw when disease cuts off the supply coming from without. Externally there is the skin for a covering—sometimes furnished with an exterior coating in the shape of hair, wool, or fur, to preserve the heat generated by the bodily workshop for its comfort and protection against external injuries. There are the nails for protecting the finger ends in man; for seizing prey or repelling enemies in the case of wild animals; the organs of sight, hearing, touch, and smell, as sentinels and sources of pleasThe body as a workshop takes in raw material in the form of food, and manufactures it for its own behoof. The same article of nourishment, being of one constitution, is taken into the body, and by its magical processes is manufactured into a supply for the waste of every part of its own machinery-bones, muscles, joints, flesh, hair, vitreous humors of the eye, tympanum of the ear, eye lashes, nails of the fingers and toes, and innumerable other portions of the system. The elaborative processes of life analyze the articles taken into the stomach, where the proper elements are segregated from the rest and manufactured into the appropriate nourishment for the growth, maintenance, and repair of each diverse organ. Nothing would seem more astonishing than the process of natural manufacturing of the most diverse products from a single kind of food material, were it not for the fact that it is so common that, like all other wonderful processes of nature, their familiarity prevents them from arresting our attention. And unlike the instruments of human industry this one renews the loss occasioned by the wear and tear of its own operations; thus keeping up its own efficiency.

THE MOST PERFECT ORGANISM IS THAT WHICH

REPAIRS ITS OWN WASTE.

The machine, skillful as it may be effected by man's ingenuity, wears out and cannot counteract this tendency; for every sort of

work it does exhausts so much of its energy.

But the machine

of the body repairs itself while continuing its work. Nor can any device of human industry make more than one kind of fabric by the same set of tools operating upon the same raw material. But here we have many that are already known and described, and doubtless many more nutritive substances which are yet unknown to science. The organized system that can effect such diversified and contrary results, and yet make them all coöperate to one general purpose, must have a degree of subtility and accuracy wholly beyond human attainment; and shows an adaptation, a unitary arrangement of parts to the whole, and to diversified results, which far transcends the grandest efforts of man.

RECIPROCAL ACTION THE CLEAREST PROOF OF A PERFECT ORGANISM.

But the converse, or reciprocal, action is equally conspicuous and quite as wonderful. Each of the different factorsthe blood, bones, muscles, flesh, skin, nails, all and several have a coördinate action. These several parts which are nourished and caused to develop are necessary to the well-being of the entire system. They are constituent parts of the machinery, which, as a whole, has its appropriate functions that could not be effected without the coöperation of each part. There are some machines so constructed that they can be reversed, and so move in an opposite direction. But they can move only in one direction at one time; and the work which has been done by direct action is counteracted or destroyed when the reverse movement occurs. But in the animal machine both processes take place at the same time in normal action. It is only when destruction or dissolution is being effected that action is exclusively in one direction. In proportion as the healthy process is active and energetic, in the same ratio will the direct and reverse movement be efficient. The more that is manufactured and therefore the more wear and tear of the machinery, the more nutriment is furnished to repair the loss. Hence, in this complex automaton the more there is lost the more there is