foiled, as if undergoing multiplication by division. The true pus-cell presents the conditions of the latter, exhibiting a more or less distinctly trefoiled or reniform nucleus. These several forms of cell in the case of those epithelial textures which are composed of numerous layers of cells, as the bronchial mucous membrane, may be seen almost simultaneously, or at any rate in very rapid succession.

Whenever a disturbing cause, irritative or inflammatory, exercises its influence on epithelial membrane, these appear to be the successive modifications which the cells undergo.

There is, however, one circumstance connected with these modifications of the cellular elements of mucous membranes which must be kept in view. It is the relative frequency or infrequency of the pus-cell from these epithelial structures. It is very common from some, equally rare from others. It is very common from the whole length of the pulmonary mucous membrane, from the pelvis of the kidney, from the ureters, bladder, or urethra. It is equally rare from the gastrointestinal track, or from the tubuli uriniferi.

The explanation of this fact is found in the arrangement of the cellular elements in these several varieties of epithelial

structure.

In the first-named parts the cells are superimposed in a succession of layers. (Plate XI, fig. 4.) Any disturbing cause leading to the shedding of the first series, and continuing its irritating influence, prevents the cells beneath either from arriving at maturity, or so modifies their development that a succession of transitional cells follows; and where the irritation assumes the form of the so-called inflammatory action, the pus-cell is produced in great abundance.

The formation of these cells, it may be observed, is not at the expense of the integrity of the tissue out of which they are formed.

On the other hand, in the gastro-intestinal and renal layers the epithelial cells occupy but a single row, and are developed directly from the germinal or basement membrane. Hence, although they undergo transitional states, passing from the true

cell to the granular and mucous cell, they rarely possess the character of the pus-cell, and when they do so can only become developed at the expense of the subjacent tissue, or, in other words, can only be formed by an ulcerative process, with loss of substance.

To return to the subject of the condition of the cells in other organs in Bright's disease.

If we now turn to the inner parts of the body, when a post-mortem examination permits us to investigate the state of parts hidden from us during life, in all those cases in which fluid has been present in the abdominal cavity, the abdominal serous membrane presents an opaque aspect, different from what we witness in cases, for instance, of violent death, where this membrane looks translucent and clear, smooth and shiny.

If a portion of the peritoneum be scraped, the wavy fibrous structure and the tesselated epithelial cells have always appeared to me highly granular, participating in the general cloudy character of the epithelial cells elsewhere.

But the surface of the heart-the exocardium-particularly in the majority of cases of morbus Brightii, exhibits those wellknown spots called the macula albida, shining, opalescent, and opaque patches, of which pathologists have noticed two varieties -one variety looking like a morsel of false membrane laid on and adhering to the subjacent serous surface, with a welldefined margin, which can be raised and peeled off. These appear to be in the nature of inflammatory products, although the history of the case rarely yields any evidence of any antecedent pericardial attacks. This form is, however, infrequent as compared with the next, in which the opacity gradually merges into the surrounding tissue. There is no appearance of a raised edge, and the patch looks simply like a milky white stain.

The tesselated epithelium of this surface is lost, and in its place nothing but a débris of granular matter can be seen, interspersed with coarse interlacing fibres, which seem to inclose the granules, together with numerous fat-granules.

(Plate XII, fig. 1.) The muscular walls of the heart are not usually unhealthy looking to the eye, or flabby in texture. These conditions would prove nothing; but if a careful microscopic examination of the muscular substance be made, proof may be obtained that here also is degeneration and decay. There is a universal tendency to fatty and granular degeneration.

The muscular striæ, instead of being clear and distinct and well-defined, are studded with granules, which here and there, in the larger form, become resplendent and highly refractive, presenting all the character of a fatty débris, which they really are, as may be clearly proved by the action of ether, which quickly removes them, leaving the fibrillæ naked and destitute in these spots, of all indications of striæ. (Plate XII, fig. 2.)

Not only is the evidence of degeneration to be observed in the muscular structure of the heart-both in ventricles and auricles-but oftentimes opaque spots are seen studding the commencement of the aorta, and extending in patches, to a greater or less extent, throughout the vascular system.

Figs. 3 and 4, Plate XII, represent the microscopic appearances of one of these so-called atheromatous patches. It reveals the presence of much fatty débris, with here and there a plate or two of chloresterine. Fig. 4 represents a vertical section through one of these aortic patches. Both were taken from chronic cases of morbus Brightii.

The liver, in the majority of fatal cases of morbus Brightii affords unequivocal proof of the disturbance which this organ suffers. Every cell appears loaded with fat. No pigmentgrains are present, but the liver-cells appear overcharged with large, round, resplendent fat-granules, giving such a fatty character to this organ, that bacony liver is the term often applied to it. The ordinary appearance of the liver-cell in morbus Brightii is represented in fig. 5, Plate XII.

If one of the minute nodules from the surface of a kidney in almost any form of morbus Brightii except the acute form, be separated and examined with the microscope, the convoluted

tubes appear filled with detached cells, surrounded by a fine granular matter, with here and there fatty débris scattered among them. (Fig. 6, Plate XII.)

May we not now appreciate the significance of that form of dropsy which, associated with albuminous urine as one of its earliest and most easily recognised conditions, pervades all the tissues, infiltrates every cell, interferes with and stagnates every function, and oftentimes becomes the immediate cause of death, by literally drowning the individual in his own fluids.

But, furthermore, this form of dropsy signifies a wide-spread deterioration of cell development; it signifies, not a local disease of the kidneys, but a decay and depreciation of tissue everywhere. For if we obtain evidence of deviations from so many remote points, we may safely infer that a like decay or deterioration of structure exists elsewhere.

The progressive transformation of the epithelial structures in unfavorable cases of renal dropsy is therefore to be accepted as evidence of a diffused and general degeneration and decay, as well as of a local and special disease of the kidneys. It is by keeping this fact constantly in view that we may hope to establish a definite principle of treatment; not directed exclusively to the kidneys, as the apparent failing organs; but to the constitution generally: aiming at the restoration of the blood to a condition favorable to a more healthy cell-development, with the hope that those functions which a retrogressive cell-formation has impeded, will speedily be re-established so soon as the vital fluid has returned to a standard condition of health.

If these facts be duly estimated, their influence over the principles which should guide the physician in the selection and employment of remedies, will be most beneficial; and I think it may not be presumption to conceive that the success which attends the more modern treatment of these dropsies, as compared with the results of past days, may be confidently traced to a better appreciation of the widespread character of the morbid processes, rather than limiting them to a local disease of the renal organs.

CHAPTER VIII.

THE VARIOUS FORMS OF DISEASED KIDNEY OF WHICH EXAMPLES ARE GIVEN IN THE FOLLOWING PAGES.

THE following are the several forms of diseased kidney, connected with dropsy and albuminous urine, which I have had an opportunity of studying microscopically, as well as of examining the urinary sediment during life. They belong to the pathological series, which is entitled to the generic name of morbus Brightii, from the distinguished physician who first described them. I do not venture to assert that they represent different stages of one disease. Although the first, second, and third forms, with great probability stand in that relation to each other; the first two representing the acute, and the third the chronic stage, I would rather say that the whole group may be viewed as examples of the direction which degeneration of structure takes when the impaired or weakened vital force is specially manifested in the kidneys; and though considerable variation in external aspect, volume, and weight are apparent, yet, nevertheless, each exhibits a similar tendency to celldeterioration, differing more in degree, than in form.

I. The red, chocolate, or plum-coloured kidney, somewhat increased in weight, the cortical surface studded with deepcoloured arborescent vascularity; the same evidence of congestion pervading the whole organ. It represents the stage of inflammatory engorgement. The Malpighian bodies are seen filled with extravasated blood; or these, as well as the convoluted tubes, are distended with a fine molecular exudation or deposit, deeply stained with hæmatin.