syphilitic origin that come under notice are due to changes closely allied to those which occur in chronic inflammation with enlarged kidney, which has been considered to be interstitial or intertubular in its origin; but the particles of bioplasm are of peculiar, and, as is said, specific character. These particles of syphilitic bioplasm are small and granular, but I know of no means by which they can with certainty be distinguished from the particles of bioplasm which grow and multiply interstitially in ordinary inflammation. It is probable that these particles of living matter, like those in ordinary inflammation, after growing and multiplying for a time, die, and undergo disintegration and liquefaction. The state of blood which results from the longcontinued introduction of small doses of mercury and of iodide of potassium, no doubt favors the death and disintegration of these particles, and promotes the absorption of the resulting products.

ALBUMEN IN THE URINE DEPENDING UPON FATTY DEGENERATION OF THE KIDNEY.

The opinion has been expressed by some that fatty kidney is invariably preceded by ordinary inflammation with enlargement; that the fatty degeneration constitutes a secondary series of changes which may be succeeded by wasting, or may destroy life before attaining this stage of pathological degeneration. That this is correct in some instances there is no doubt, but in the opinion that the large, white, fatty kidney occurring in children and young people is invariably the result of acute inflammatory affection I cannot concur, for one often sees cases where the change has gradually proceeded for many years without any acute or sudden derangement of the health from first to last.

In several forms of renal disease, with the exception of amyloid kidney, fatty degeneration affecting some of the epithelial cells as well as the walls of the capillaries and other tissues, is very frequently observed, and in varying degree. There is, however, one form of disease to which the term "fatty kidney" is properly applied. It occurs, for the most part, in young

people, is probably developmental in its origin, and in all but a few exceptional cases, in which only a portion of the kidney is involved, is fatal, generally within four or five years from its commencement. The urine of these cases contains usually a large quantity of albumen, generally amounting to a third or half the bulk of urine subjected to the influence of heat or precipitation by nitric acid. The urine is pale and of low specific gravity, from 1.005 to 1.015. There is usually a whitish deposit, which gradually subsides, and is found, upon microscopical examination, to consist of tube casts containing oil globules and epithelium filled with oil globules, free epithelial cells and free oil globules, and small collections of the same. As these cases cannot be cured, all we can hope to do is to retard the progress of the disease, and prolong life for a time. As the disease advances, the blood becomes poor in red corpuscles, and the surface pallid. Dropsy supervenes, and as time goes on the patient suffers from distressing vomiting, and death sometimes results from exhaustion, sometimes from uræmia and coma, and is sometimes accelerated by the occurrence of pericarditis; occasionally the case is complicated by the occurrence of pneumonia or pleurisy, or both.

Fatty kidney is a very fatal form of kidney disease. I must, however, state that recovery occurred in two cases (girls under twelve), in which all the symptoms of large, pale, fatty kidney were most marked. The urine contained a large quantity of albumen and numerous casts containing oil and free cells crowded with oil globules. There was general dropsy with vomiting and pallor, lasting for several months. Preparations of iron were given in both these cases, and after the lapse of five or six months the patients began to improve. In these cases and others of the same kind to which my attention has been drawn, I think that probably only a portion of one kidney was affected, and that as the general health improved, the fatty degeneration ceased to extend. The tubes already affected probably slowly wasted, their place being taken by new tubes which were gradually developed. Although it would be unreasonable to suppose that where the renal structure generally of both kidneys was

the seat of fatty degeneration, recovery might occur, it is certain that in many cases the morbid change begins in one part and slowly progresses. If, therefore, the condition is detected at the commencement, and the state of the patient's general health can be completely changed, it is reasonable to suppose that the disease may be arrested, the disintegrated secreting structure replaced by new tissue, and even complete recovery take place.

ALBUMEN IN THE URINE DEPENDING UPON AMYLOID OR
LARDACEOUS KIDNEY.

In waxy amyloid, lardaceous or albuminoid degeneration, we have a series of very remarkable morbid changes, the origin, causes and precise nature of which are still obscure. The kidney is larger than normal, having on section a peculiar transparent appearance, the cortex pale, the pyramids dark, in consequence of the vasa recta and the veins being injected. The texture is firm and brawny looking, giving the idea that the tissues are suffused with transparent material. The surface of a section becomes white on being moistened with nitric acid, from the large quantity of albumen present. Iodine exhibits a peculiar reaction, and stains all the tissue of a deep brown color. The transparent amyloid matter which gives these reactions is deposited first in connection with the smaller arteries, and particularly the vessels of the Malpighian body, the coats of which are in consequence much thickened, irregular in their outline, and having their calibre in some places much reduced; while in others the tube seems to be dilated. The tubes are very tortuous, and one branch can sometimes be followed for a long distance as it twists about in the semi-transparent tissue. The loops of the vessels of the Malpighian bodies are early affected, but the capillary walls are also thickened from the deposition of the same substance, and as the disease advances, every part of the renal tissue becomes infiltrated. The epithelium of the tubes is altered, and a quantity of the glistening material often occupies the cavity of the tubes, and escapes from time to time as long, elongated cylindrical casts, around which

new layers are deposited as they pass downward toward the pelvis of the kidney. Several have been figured in "100 Urinary Deposits," Pl. IV, Figs. 49, 50. The tissue of the tubes, like that of the vessels, becomes stiffened by the deposition of the transparent matter, and the tubes are, therefore, freely open for the passage of casts, or any exudation that may be poured out. The morbid change affects other organs, and the liver and spleen usually exhibit the morbid change in remarkable degree. They may attain a large size, and not unfrequently before the kidneys begin to be invaded. The vessels of the Malpighian body seem to suffer first, and from the appearances resulting, it is probable that the glistening substance is deposited as the fluid which holds it in solution gradually filters through the tissue.

At first there is no oedema, either of the most dependent part of the body or of any tissue, but as the disease advances it appears and gradually extends. Many of the textures become infiltrated with fluid, and in the liver all the tissues suffer from its presence. The hepatic tissue occupies a greater bulk than in the normal state, and its specific gravity is lower than that of healthy liver. Ascites not unfrequently appears, and in some cases fluid accumulates to a very great extent. The quantity of urine is increased, and in some cases to a considerable extent. It is usually of low specific gravity, and contains albumen, which increases as the disease advances.

Amyloid kidney occurs in persons of phthisical constitution, prone to the occurrence of caries of bones, and scrofulous abscesses, and in those who have long suffered from extensive chronic suppuration or from certain forms of syphilis.

In amyloid kidney the blood is poor and pale in color, and it is probable that the glistening albuminoid material is formed in it. After a time tissues and organs become infiltrated, and the transparent matter is deposited in connection with the tissue, while the fluid is reabsorbed into the blood. The disease may last for many years, but it is very doubtful if recovery occurs after the morbid change has once become established, although it is quite conceivable that in the very early period of the change good air and careful attention to diet may be very beneficial,

and even that a state of system might be established in which the absorption of the amyloid matter already pervading the tissues might take place, and the matter itself be removed and eliminated.

Casts are very commonly present in the urine of amyloid kidney. Some are composed of glistening, wax-like material and flattened epithelial cells are sometimes attached to them. New matter is added as the cast passes down the tube, and it is not uncommon to meet with specimens which consist of several layers superposed upon the original cast. It is more probable that the new matter thus deposited circumferentially exudes from the wall of the tube, and is deposited as the cast passes along, than that it escapes from the vessels of the Malpighian body, and is thence conducted into the tube.

ON THE TREATMENT OF DISEASES OF THE KIDNEY.

By the careful and minute study of renal physiology and pathology we hope to be able to distinguish those cases of renal disease which it is possible to relieve or cure, or which may be restored to health by remedial measures, from those which are absolutely incurable--and among the latter to distinguish those which will be rapidly fatal from those which are likely to become very chronic and last for many years.

Those who are familiar with this class of diseases know that cases have been needlessly condemned which have made complete and rapid recoveries. On the other hand, persons suffering from certain serious and fatal forms of the disease in which there were no observable general symptoms, who have scarcely believed themselves to be out of health, and have even been recently accepted by Insurance Offices as perfectly healthy lives, have succumbed within a few weeks. The diagnosis between many slight and serious maladies of various kinds, although still far from precise, is, thanks to modern investigation, becoming more and more practicable. Even in the case of renal diseases, which, in their course and progress, are among the most uncertain with which the practitioner has to deal, something approaching precision, as regards prognosis as well as diagnosis, is attain