tines of animals after the removal of the kidneys, and in the matters vomited by patients affected with cholera; also in certain cases in the blood, and in the exhalations; but the bearing of these facts was not appreciated till Frerichs demonstrated the truth of the following propositions: 1. That in every case of uramic intoxication, a change of urea into Carbonate of Ammonia takes place. 2. That the symptoms which characterize uramia can all be produced by the injection of Carbonate of Ammonia into the blood." In his experiments he "has frequently detected the alkaline salt in the expired air of animals deprived of their kidneys, and into the veins of which he had injected urea; these animals remained quiet and awake as long as the expired air was not impregnated with the Ammonia; but the moment the latter was observed, the various disorders of the nervous system characteristic of uræmic poisoning developed themselves. These views of Frerichs will necssarily tend to the settlement of a 'vexed question, which has called forth the ingenuity of both the physiologist and chemist. It may, however, be that the future will reveal the existence of other poisoning materials in the blood which, to the present time, have eluded observation; and in their recognition we may find additional causes for the production of toxæmia. It has indeed been suggested that, in Bright's disease, the accumulation of oxalic acid. in the blood will develop the symptoms of uræmic intoxication.

In cases of puerperal convulsions Brann attributes the death of children to the same cause as that of the mother who dies from uræmic convulsions, viz.: to poisoning by Carbonate of Ammonia, which poison is found in the fœtal blood.

In Nov. 1860, Dr. Richardson read a paper on this subject before the Medical Society of London, in which the following points of interest are presented:

DIAGNOSIS.-The pupil is usually fixed in uræmia, and in most cases is dilated, though in one case it has been seen contracted to a pin's point. Frerichs has said that there is evidence of excess of Ammonia in the breath during the acute attack; but this is not universal, for in persons suffering from kidney-disease, and in whom uræmia is a probable occurrence, the breath at the best of times is charged with. Ammonia to an extent greater than is normal. In these cases the lung is supplemental to the kidney, each organ trying to eliminate all it can of the accumulating poison. If such a patient takes congestion of the lung, the elimination from the lung is suspended, and then uræmic symptoms advance. In some examples the suspension of the secretion from the kidneys is sudden, and uræmia suddenly follows, and the breath becomes suddenly amoniacal. Another characteristic of the coma from uræmic poisoning, as distinguished from that by poisonous doses of narcotics, is that the patient under the former will often rally and

VOL. II.-49.

regain all his consciousness for a time, sinking again into forgetfulness and even dying unconscious in the end. The poison may not be simply urea, it may be some combination of ammonia into which carbon enters, as the carbonate. (See Diseases of the Kidneys.)

GENUS II.-LITHIA.-URINARY CALCULI.

A satisfactory explanation of all the phenomena attendant upon the formation and development of calculous concretions in the kidneys and bladder has not yet been given. Chemistry has, indeed, afforded us much accurate knowledge respecting the composition of the different varieties of calculi; but we still remain in ignorance of the real causes and nature of the abnormal action, the peculiar condition of the organism requisite to originate this action, and of the specific medicines capable of effecting cures. The data upon which modern physicians have founded their prescriptions may be more scientific and accurate than those of the ancients, but we are not aware that the practical results which they have obtained are in any great degree more decided or favorable. The ancient allopathists attributed the formation of stone to the union of the "terrestrial and tartareous parts of the blood with the clamminess of the vicious lympha, that continually flows by with the urine, and further compacted together by the salts with which the urine is laden." (Salmon.) And for the cure they prescribed venesection, opiates, mercurials, diuretic infusions, and decoctions, and "lithontriptics," or "stone-disssolving remedies." Modern allopathy attributes calculous depositions to a superabundance of uric-acid of the phosphates of lime, magnesia, and ammonia, oxalate of lime, &c., in the blood and urine, and they also prescribe bloodletting, opiates, mercurials, diuretics, and "stone-dissolving remedies," but with no more success than their heathen predecessors. To what extent homœopathy may be able to combat this formidable disease, further time alone can determine; but so far as the observations and experience of our practitioners extend in this class of affections, our method of practice has been highly satisfactory. Our system is especially adapted to correct those peculiar diatheses upon which the formation of calculi depends.

Calculous affections have been observed to prevail in some countries more than others; even in some portions of the same country they may be common, while in other sections they will be unknown. The disease is rarely seen in very cold or very hot latitudes. English surgeons assert that it never originates in the East Indies, and it is supposed to be of very rare occurrence in the Northern kingdoms of Europe.

Children and old people are not subject to the disease, and it seizes especially upon those in whom gout is hereditary. Indeed, this gouty

diathesis is so common in individuals afflicted with calculi, that many suppose that the urine exercises but little if any influence in their formation, but that metastasis of gout to the mucous membrane of the urinary passages, determines the formation of these calculous concretions. Thus, Frank, in his "Traité de Pract. de Med., p. 367, Vol. II, says: "The attacks of calculous affections, like those of gout, are preceded and accompanied by languor of the stomach, nausea, oppression, eructations, borborygmi. In inveterate gout, this plegmasia gives rise to calculous concretions, formed of a material combined with uric-acid, and which do not differ from urinary calculi, except in consistency and form. Suppose now that fixed gout, which produces calcareous concretions in the articulations of the great toe, attacks the mucous membrane of the bladder, may it not become the source of calculi in this viscus?"

Calculi have been found in the brain, lungs, bladder, liver, spleen, gall-bladder, uterus, the articulations, and the soft parts of nearly every portion of the organism; but the urinary organs are by far the most common seat of these formations. Several years since we saw taken from the upper part of the left lobe of the lung of a miller, two concretions of a chalky appearance, but hard and tough, and of the size of a goose-egg. Concretions of lithate of ammonia are also common in all parts of the body in gouty patients.

Prout has divided the mechanical deposits from the urine into three classes: First, pulverulent, or amorphous sediment. Second, chrystaline sediments, usually denominated gravel. Third, solid concretions or calculi, formed by the aggregation of these sediments.

The sediments of the first class are held in solution by the urine until it is discharged from the bladder, when they are gradually deposited in a state of fine brown or yellow powder. These sediments are generally composed of "two species of neutral saline compounds, viz.: the lithates of ammonia, soda, and lime, tinged more or less with the coloring principle of the urine, and with the purpurates of the same basis, and constituting, what are usually denominated pink and lateritious sediments; and, secondly, the earthy phosphates, namely, the phosphate of lime, and the triple phosphate of magnesia and ammonia, constituting for the most part, sediments nearly white. The two species of sediments are frequently mixed together." (Prout.) The sediments of the second class, or gravel, are found in the urine in regularly crystalized grains, varying in form and color in accordance with the constituents of which they are composed. The lithic acid crystals are much the most common, and may be distinguished by their red color. The crystals of the triple phosphate of ammonia, and of magnesia, are of a white color, while those of the oxalate of lime are black or dark green.

Prout supposes that two-thirds of the whole number of calculi originate from lithic acid; and when we bear in mind the constant presence of this acid in the urinary organs, and its proneness to form hard, inodorous concretions, of a yellowish brown color, the supposition will not appear unreasonable.

Chemists have described many different varieties of calculi; amongst which the following are the most common:

First. The lithic or uric acid calculus, formed by concentric lamellæ, presenting a light-brown or reddish color, and a general appearance something like wood. These calculi are infusible by the blow-pipe, but may be slowly evaporated, until a white residue of white ash remains. They are soluble in alkaline solutions, which, on this account, are supposed to be valuable as remedial agents; but they are not dissolved by muriatic or sulphuric acids. The lithic acid diathesis prevails in childhood and at about the age of forty or fifty, and the urine voided in these cases is generally acid, and the deposited sediment of a red color.

Second. The calculi of most common occurrence after the variety last described, are those composed of a triple combination of phosphoric acid, magnesia, and ammonia. They are of a lightish gray color, indistinctly laminated, with an "uneven surface, and covered with small shining crystals." This variety is not soluble in alkaline solutions, but may be partially dissolved by muriatic, nitric, and sul phuric acids, and imperfectly fused by the blow-pipe. The urine in this case is very foetid, and the sediment deposited of a white color, "resembling mortar." Sir Astley Cooper asserts that this kind of calculus is very apt to be reproduced after lithotomy, and on this account advises the postponement of operations in these cases until the morbid diathesis is corrected.

Third. Not a very common variety is the mulberry calculus, of a dark-brown color, uneven surface, and very compact, heavy and hard. It consists of oxalate of lime, and is partially soluble in muriatic and sulphuric acids, but the alkaline solutions have no effect upon it.

Fourth. The phosphate of lime calculus is in a few instances found pure, but usually it exists in combination with uric acid and phosphate of magnesia and ammonia. It is laminated, polished, of a pale-brown color, soluble in muriatic or nitric acid, and may be fused by the blowpipe. They are of small size, and are generally found in the prostate gland.

Fifth. The cystic oxyd calculus is another variety of rare occurrence, of a yellowish hue, not laminated, soluble in acids and alkaline solutions, and emitting under the blow-pipe a foetid odor.

Sixth. There is also the fusible calculus, composed of a mixture of the triple phosphate of magnesia and ammonia, and of the phosphate

of lime; of a white color, and fusible by the blow-pipe. This kind of calculous deposit is occasionally seen between the prepuce and glans penis in old cases of phimosis.

Seventh. The constituents of different kinds of calculi are sometimes deposited in distinct alternate layers in the same stone, when it is called the alternating calculus.

Other varieties have been described, like the compound calculus, the lithate of ammonia calculus, and some others.

The presence in the bladder or kidneys of any solid substance, whether introduced artificially, or formed naturally from lithic acid congestions, or clots of blood, favors the formation of calculi. Whether the cause of these deposits in the urinary is attributable to the peculiar composition, or the compact structure, or the comparative temperament of nuclei we are unable to determine; but all are aware of the fact, that catheters, bullets, splinters, or any other solid substances accidentally introduced into the bladder, become speedily coated over with urinary sediments, which are converted into hard crusts.

Calculi are more frequently observed in the male, than in the female sex; but this circumstance has been attributed to the difference in the structure of the urinary organs. The urethra of the female being shorter and easily dilated, gives passage without difficulty to gravel and small calculi, which in the long and contracted male organs would be obstructed either by causing spasmodic contractions, or from an actual want of room to pass.

It is said that the right kidney is far more commonly the seat of these formations than the left, that there form is generally spheroidical and that their average weight is from one to two ounces. Sir Astley Cooper, however, expresses the opinion that the majority of urinary calculi weigh less than one ounce each.

Calculi may originate in the kidneys, the bladder, or the prostate gland, but the first organ is the primary seat of a large majority of cases, as is evident from the fact that the pains are almost always confined to the region of one of the kidneys in the first instance. It is probable that the nuclei of most stones found in the bladder, are first formed in the kidneys, and then conveyed through the ureters into this viscus to serve as the foundation of still further deposits from the urine. We have seen a stone formed on a cedar pencil.

DIAGNOSIS.-A calculus may remain in the kidney or bladder for a long time, without exciting much pain or uneasiness. The patient experiences perhaps a more frequent inclination to urinate than natural, and after violent exertion on horseback or in a carriage, has temporary pains in the region of the organ affected, but in other respects he feels well. This state of things may exist for an indefinite length of time, when, if the stone is situated in the kidney, some exciting cause may