the cell must attack it at its vulnerable points, which must be its top, and thus destroy the newly adjusted or adjusting finites. Cells are not always in vertical lines; one cell may be the parent of many, or, on the contrary, many may merge into one, presenting the appearance, not inaptly, of a woman narrowing or widening in knitting. They sometimes present gentle curves, as in the ball of the eye, lymphatic glands, etc. In certain localities they are firm, contracted and inelastic, as in the tendons, cartilages and bones, nerves, muscles and heart, and other kindred parts. In other sections they are exceedingly mobile, pliable and elastic, as in the mouth, glands, stomach and uterus. These differences of wall structure are absolutely necessary to complete the multiplicity of needed actions and functions in the cell-life throughout the entire body.

Excretory and secretory, or in other words afferent and efferent, cells are more or less cylindrical and elongated, and act as sewerage-pipes, expurgating, purifying and separating impurities from the system, or as channels of affection, induction, recuperation, adjudication, appropriation, organization and sustentation.

Recuperation or repair of structure as is exhibited in the loss of superficial tissue, is truly wonderful. From the newly made wound to the completion of the cicatrice is as much of a mystery as an individual creation itself. Behold the gaping wound, continuity destroyed, important vessels severed and contused. Now apply your very best microscopic appliances, and observe the white blood-corpuscles as direct evidences of cellules, freighted with the finest of nutrient material, almost too pure for even microscopic vision, the real spirituous formative substance of nature seeking to repair the loss. Soon granules form in rapid succession and the breach is restored by first intention. First you behold the blood-corpuscle, then the plastic lymph, then minute granules, with interstitial plasma uniting and aiding in the required work until the last cell is completed, and nonformative lymph as an incrusting protection is poured out to guard the finer parts within until able to bear the requirements of general life. But should the granulations become too large and spongoid in consequence of too much local nutrition, the result is, eventually, suppuration, or disintegration of these morbid growths. The

granules proper are, when cut into, limpid, pure and lymphlike, while the spongoid granules (called proud flesh) are cloudy, apparently floccular and serous, thus showing a beautiful difference between pure, healthy formative cell-life and that life perverted. Each granule is a cell closed over, but the succeeding cell proceeds out of and directly from the one prior to it in formation. Sometimes a beautiful, regular row of sparkling granules, or celluloidea, arranged on either side of the fleshy chasm, are sufficient to bridge over and unite the edges without any excess of material whatever. Here Dame Nature works almost unobserved and unmolested. In darkness, secrecy and silence, little by little, were all the worlds made and all that therein is. The coral reefs and islands, the fossil coal-fields and our present forests are constantly attesting the verity of cell-life, and we are no exceptions to this general law. "In the midst of life we are in the midst of death," is and has been an axiom from time immemorial, accepted by all alike, the fool as well as the sage.

Having therefore contemplated life in the cell, let us not forget to meditate upon its death. Having lived it must die, and in dying it only prepares to live again. Finites, like histories, repeat themselves. Defective, deficient and inappropriate nutrition will blanch, atrophy, impoverish and paralyze every cell under its blighting influence. While excessive, overnutritious and morbid appropriation of nutrition will cause growth of fat, tumors of every conceivable form and character, harmless and malignant, cancroids, eruptions (volcanic), cancers and hosts of other morbific addenda, which need not be even hinted at in the long catalogue of cellular pathology. Injuries as well as misapplied nutrition do much to misdirect cell-life. Injuries contuse, obstruct or destroy the cells, which must be either repaired, removed by suppuration or spring up into morbid growths, the atropa of life. Examine the cells of whatever morbid growth you desire, whether in the vegetable or animal, and you will never fail to see them. Abnormal as to size, shape, form, general appearance and function; here arranged in circles, there in arborescent display; here in zigzags, there in straight lines; here in nebulæ, there as isolations or local foci; here diverging, there converging. Here you behold some cells quite large, spongoid

and softening previous to total depravity, there you observe, on the contrary, cells of hardened diminutive character; they are not entirely vitiated, but are really resisting the ravages of the disease.

Such are some of the appearances of cellular pathology. They are not fancy sketches by any means, but may be seen whenever sought for in all morbid growths. The cell often dies from within first, as the contents diminish, dry up and pass away, or from contraction, softening, disintegration and decay of its walls.

Cell walls are often broken down en masse, particularly in carcinoma, contused wounds and in extensive syphilitic sloughing ulcers; but as a general thing the segregation of the dead from the living cells is done singly. In all local inflammations resulting in the suppurative process, the alteration of the cells from the normal standard is coextensive with the inflammatory action. And the same law obtains whether in peritonitis, enteritis, gastritis or any other internal organ or tissue. The cell first suffers individually, then generally. But why extend the subject any farther? It is ubiquitous, without either centre or circumference, and hence exhaustless. I have given you but at meagre initiatory instalment of the inexhaustible mental sweets kept in store for all the votaries of the microscope.

If I have induced but one person in this assembly of observers and thinkers to visit the field and labor for light, I have accomplished my purpose. You need not wait for a suitable opportunity, or look around you in extenso for a favored spot or subject; they are all present with you, every where, anywhere and allwhere. Just think of it. The whole universe is composed of finites, molecules and cells. A simple trinity of principles constituting the complete skeleton of the whole world and all thereunto belonging, covered and beautified with the same. Ought not every physician be a scientist, physiologist and pathologist of the most zealous kind? It would be a feast of fat things upon the lees; not spontaneous generation, but generation from inflowing life, filling the will and understanding with a true knowledge of the little things of nature, their relations to each other, himself. and the rest of the world.

III.

MICROSCOPY OF THE BLOOD.

BY C. P. ALLING, M.D., Dunkirk, N. Y.

A VITAL or nutritive circulating fluid is a constituent in every living organism. Without it there could be no manifestation of the phenomena we term life. This fluid is called the sap in plants, in animals the blood.

Blood is formed from materials contained in food by the processes of digestion and assimilation, being modified by oxygen received through the function of respiration. It has a certain viscid appearance, a density considerably greater than water, color, the particular hue of which depends upon the portion of the current whence it is drawn, and a number of accidental influences which sometimes affect the hue, such as impure air, anaesthetics, disturbed respiration, inflammation and the like. The specifie gravity varies from 1050 to 1059, the average being 1055 in normal human blood.

The chemical reaction is invariably alkaline, and if I mention a taste like salt, and a certain faint odor resembling the exhalations from the lungs and skin of the individual from whom it is drawn, I have recited all the characteristics discernible by the unaided senses.

When examined under the microscope, however, this apparently homogeneous fluid, even while coursing through the blood vessels during life, is seen to be composed of a mass of circular or oval bodies floating in a clear and perfectly transpar

ent liquid. These minute bodies are known as the blood-corpuscles, and the containing fluid is called the blood plasma or liquor sanguinis. It is with the former that the microscopist has principally to deal.

In human blood the greater number of these corpuscles are colored and disk-shaped; that is, they are circles with flattened sides. They are from 200 to 300 of an inch in diameter, the average being perhaps 32'00. In thickness they are only

400 of an inch. The flattened sides are somewhat concave in the natural state, making the disks thinner at the centre than at the circumference. This circumstance causes them to appear like small dark rings with bright centres. By changing the focus of the lens slightly the centres become dark and the circular edges bright, thus showing that they do not lie in the same plane. This appearance has been by some observers mistakenly supposed to indicate the existence of central nuclei.

Of the question whether human blood-disks are nucleated, there is a difference of opinion among histologists. Reasoning analogically, it is clear that nuclei should be found, but it is equally certain that they cannot be seen by ordinary means of illumination. My friend Professor J. Edwards Smith claims that he can show the nuclei in about three-fourths of the disks, viewing them as opaque objects, illuminated by means of his improved Beck's vertical illuminator and with a very wide-angled lens. This is in keeping with my own idea that the newly formed disks are non-nucleated, but in advanced life of the corpuscle a nucleus is formed.

Besides the red blood disks are also found a few colorless bodies, which are known as the white blood-corpuscles. They are globular in form, larger than the disks, and unlike them contain from one to three nuclei, which are about of an inch in diameter.

The relative number of the leucocytes or white blood-corpuscles varies under different circumstances. Thus, according to Welker, a celebrated German authority, we find 1 white corpuscle on an average to 335 red ones, while Moleschott states the proportion to be as 1 to 357. From my own observations I am inclined to think the number overestimated by both, as I have