by most physiologists to be three. 1. The water taken into the alimentary canal with the ingesta. 2. Those soluble substances which are taken in the same way, and which do not undergo decomposition in passing through the extreme circulation, e. g. the neutral salts of metallic bases with mineral acids, which appear to act as stimulants to the kidneys. 3. Those lower organic products which are formed in the extreme circulation, or, in the phraseology of Liebig, the products of the transformation of tissues, e. g. urea, urates, &c. In order, then, to the due secretion of urine, the following conditions are essential:-An absorption of a sufficient quantity of water from the ingesta to hold the salts, the decomposed soluble matters, and the products of the transformation of tissues, in solution: the free transit of this water and soluble matters through the portal veins, the liver, the right side of the heart, the lungs, and the left heart, to the kidneys: a healthy condition of the extreme circulation, whereby the normal product of the transformation of tissues may be duly formed: a condition of the kidneys adequate to the carrying all these matters out of the system when applied to them by the blood. If, therefore, any one of these conditions be vitiated by disease, the secretion of urine will be impeded, either as regards its quantity or the proportion of the solid contents." 397.

Appended to Dr. Barlow's paper is a short case communicated by Dr. Lever.

Mrs. P, aged 51, presented herself to Dr. L. with symptoms resembling the passage of gall-stones-excessive pain in the epigastrium, in paroxysms-jaundice-sickness-scanty urine-constipation, &c. &c. Treatment. Local depletion-calomel and opium-castor oil-enemata. The symptoms were removed, with the exception of the yellow tingeand twelve months elapsed, with constipation and indigestion.

On the 5th of August, Dr. Lever was called to her, and found her labouring under excessive pain in the region of the gall-bladder-sickness incessant-extreme yellow tinge--bowels confined-urine high coloured and scanty. Local depletion--calomel and opium-enemata, &c. But she suddenly sunk and died. The liver was found large and dark-coloured -no trace of gall-bladder-adhesions between the duodeno-pyloric orifice of stomach, and liver and pancreas. Pyloric orifice very much contracted from thickening of coats. About the middle of the duodenum a common quill could scarcely be passed through. Great contraction also obtained in the transverse descending colon and rectum, which would scarcely admit the point of a finger. About the centre of the ilium there was a biliary calculus the size of a walnut, partially sacculated.

CASE OF POISONING BY OPIUM. By Alfred. S. Taylor. (Guy's Hospital Reports, October, 1844.)

THIS is one of the numerous instances of death being caused through the administration of opium to children by nurses. The form employed was unusual, namely, an infusion, made by pouring warm water into a bottle containing opium, and shaking the mixture well up. The child (æt. 14

months) had had slight diarrhoea, and, being restless, more than three teaspoonfuls of this fluid were administered to it in a brief space of time. It soon became drowsy, and continued comatose, with the exception of a short interval. until its death, which occurred eighteen hours after the administration of the drug. The chief post-mortem appearance consisted in a very congested condition of the blood-vessels of the brain, unaccompanied by any effusion. A portion of the mixture employed, being tested with nitric acid and sesquichloride of iron, gave unequivocal signs of the presence of opium. A small portion of the contents of the stomach were analyzed, but no opium detected therein; a fact nowise surprising, when the length of time between its being taken and the occurrence of death is considered.

Mr. Taylor observes, that toxicological writers have not alluded to the degree of solubility of opium in water, although this is a question likely to be put to a witness occasionally. By experiment he found that boiling water poured upon powdered opium, had, after twenty hours, taken up 4 per cent. of its weight, and from 2 to 4 per cent. when the common extract sliced was employed. The dregs still retained poisonous properties, capable of extraction by new infusion or decoction.

Tests.-Where opium cannot be detected by the smell, the author prefers the sesquichloride of iron as a trial test, discovering as it does meconic acid in of a gr. of opium.

"It might be supposed, that if, on adding strong nitric acid to a portion of the liquid, a bright red colour resulted, this would be a sufficient indication of the presence of morphia, and therefore of opium: but a serious mistake might be committed in such a case, unless the operator had previously employed the iron test, and determined the presence of meconic acid in the liquid. It is worthy of remark that the nitric acid test, while it destroys the colour given by the meconate of iron (a dark red), will bring out, when added to excess to the same portion of liquid, the peculiar bright amber-red tint which it is known to give in a solution of morphia. The tests for meconic acid and morphia may thus be applied to one quantity of liquid."

Mr. Taylor, after explaining the fallacies these tests, and that of iodic acid, may give rise to, next describes some experiments he instituted for the discovery of the smallest quantity of morphia which can be detected by each. He found that nitric acid detected gr. of muriate of morphia, diluted in 300 parts by weight of water; sesquichlor. iron detected the gr. in 231 parts of water; and iodic acid the gr. in 1300 parts of water. Thus iodic acid is by far the most delicate test, discovering as it does morphia in less than of a grain of opium; but it is also the one most open to fallacy, and cannot be employed in coloured organic liquids, containing these small quantities. Practically its utility is far less than would be anticipated from the result of experiments upon the pure salts of morphia. Other experiments were performed for the purpose of ascertaining how small a quantity of meconic acid need be present in a fluid, to admit of its separation by acetate of lead, and subsequent identification by sesquichl. of iron. No precipitate of meconate of lead occurred when the proportion of meconic acid was less than gr. i. e. about 0.34 gr. common opium. Unless, indeed, soluble matter of several grains of opium exists in the liquid for analysis,

it will be difficult to obtain meconic acid and morphia separately. The iron test for meconic acid is far more delicate than any of the tests for morphia, and is much less liable to be interfered with. The gr. or smallest visible portion of solid meconic acid is easily detected when free, while in solution, in a small quantity of liquid, even 0 gr. may be discovered. Thus, the presence of this acid may be determined in a liquid from a much smaller quantity than would suffice to form a separable precipitate of meconate of lead; for, while for this latter of a grain of opium is required, less than grain suffices for the exhibition of the acid by the direct application of the iron test. The procural of the precipitate of meconate of lead does not increase the certainty of the iron test, but merely enables us to obtain the meconic acid in a concentrated and solid form.

ON THE ACTION OF DIGITALIS AND ITS USES IN DISEASES OF THE HEART. By William Munk, M.D. (Guy's Hospital Reports, October, 1844.)

THIS praetical paper is founded upon upwards of 400 observations, which were made during five years of dispensary practice. The tincture has been found the most successful form of preparation as regards the effect produced upon the action of the heart, while the infusion is incomparably superior as a diuretic; and, from want of attention to this distinction, discrepant opinions as to the utility of the medicine have doubtless arisen. The powder, used alone, Dr. Munk considers as worthless, and although in combination (with mercury and squill) it forms a valuable diuretic, it cannot be even so employed as a sedative.

The action of digitalis upon the heart is manifested in two ways: by the exertion of a depressing influence, and as an antispasmodic. Hypertrophy of the organ, whether simple or complicated with other disease, causing increased impulse, may be benefited by the depressing influence of digitalis, which is best obtained by giving the uncombined tincture, in tolerably full doses, at intervals of eight, ten, or twelve hours. The antispasmodic influence, acting so beneficially in the irritable condition of the heart manifested by palpitations, irregularity, &c., is that which is usually sought from digitalis. Dr. Munk does not agree with those writers who state the action of the digitalis upon the heart to be uncertain. Its operation is as certain, in properly-selected cases, as that of other medicines, and may be maintained with safety.

There are, however, circumstances under which this medicine cannot be exhibited usefully or safely. Thus, in a plethoric state of the system, its employment must be deferred until blood letting or other evacuants, for which it is no substitute, have played their parts. An inflammatory, or sub-inflammatory condition of the gastric and intestinal mucous membrane, seems to prevent the action of digitalis upon the heart; and increased irritation results if it he persisted in. Such complication of lesion

of the heart and gastric derangement is by no means rare, and in such cases prussic acid is the appropriate medicine. Quietude of mind and body much favour the action of digitalis. The recumbent posture is very adjuvatory to its depressent action; aud Dr. Lombard truly observes, that it is rarely efficacious in those who take much exercise, or whose attention is much occupied during its use. Dr. Munk gives m x. ad xxx. every eight, ten, or twelve hours, and is rarely disappointed. He does not reduce the pulse, which is to be carefully watched, below 60 in the adult, and thus derives the beneficial without risking the production of the dangerous effects.

Digitalis rarely acts as a diuretic when its influence upon the heart is marked, and vice versa. The author quite concurs in the high opinion Withering entertained of its power of increasing the flow of urine, which is seldom accomplished by any other drug after its failure. It is not to the robust, florid, or wiry-pulsed, but to the enfeebled, shattered, condition of the system that digitalis is applicable. "If the pulse be feeble or intermitting, the countenance pale, the lips livid, the skin cold, the swollen belly soft and fluctuating, or the anasarcous limbs readily pitting on pressure, we may expect the diuretic effects to follow in a kindly manner. These remarks were penned, it is true, in reference to dropsy, from whatever cause arising; but, mutatis mutandis, they are equally applicable to all cases in which the diuretic operation of foxglove is required." In diseases of the heart, a diuresis is frequently a valuable means of preventing effusions by diminishing congestion, or of producing their absorption if they have already occurred; but whether digitalis be the appropriate remedy or not, depends in chief upon whether a sthenic or asthenic condition of the system prevail. Thus in the case of hypertrophy, it is seldom appropriate, while in dilatation it is usually the best of diuretics. Valvular disease is that in which digitalis proves most useful, except in cases in which this is complicated with hypertrophy. The infusion is to be given in doses of 3ss. to 3j. every six or eight hours. With a view of preventing the sedative operation of the drug, moderate exercise, short of diaphoresis, should when possible be taken. A moderate quantity of drink may be given, and the loins must be covered with a double roll of flannel, or, as recom. mended by Lombard, a stimulating plaster may be applied to them.

Dr. Munk believes that untoward and fatal effects, resulting from the continued employment of this medicine, are "exceedingly rare ;" and cites the opinions of Drs. Holland and Pereira as confirmatory of his own.

"It has only occurred to me to see the slighter and less portentous of these symptoms as a consequence of foxglove; such as, inequality or intermittence of the pulse, loss of appetite, and frontal headache: either or all of which have at once subsided on discontinuing the medicine. I believe that such symptoms will only occur when the drug fails to act in a normal manner as a sedative or a diuretic. If either of these effects are once obtained in a kindly manner, I then consider my patient safe from the poisonous operation of the drug. If, on the contrary, it does not evidence its usual effects within a few days, the medicine, I believe, accumulates in the system, and the patient is in danger of experiencing its poisonous influence. I am therefore in the habit of prescribing it for a week: and, if within that period, I perceive neither sedative or diuretic effects, I then invariably desist from its administration. Let these effects, however, be once kindly induced, and the medicine may then be continued with safety for a con

siderable period. In no one instance have I seen a bad effect follow the use of digitalis where the first consequences of its exhibition were the removal or material alleviation of prominent or distressing cardiac symptoms, whether this has been brought about by its operation as a sedative or as a diuretic." 310.

REMARKS ON THE PATHOLOGY OF IRITIS. By J. F. France. (Guy's Hospital Reports, October, 1844.)

SIMPLE iritis, if it ever occur independently of injury, is a mere disease; and the author's remarks are directed to the consideration of the syphilitic and arthritic forms, especially the former, which is by far the most frequent of all. The early and middle periods of manhood are the ages most liable to syphilitic, while elderly persons are more often the subjects of arthritic iritis. In both, the feeble and cachectic are those who chiefly suffer, at least among the applicants at hospitals. The appearance of the iris in the two cases is very different. In syphilitic iritis the mobility and the brilliancy of the iris are soon diminished; and before long, at one or more points, its structure becomes tumefied, and its colour changed to a reddish brown. More or less exudation from the aqueous membrane attaches portions of the edges of the pupil to the capsule of the lens. The quantity of fibrin effused into the anterior chamber may be very great. It is, however, in the arthritic form of the disease that the lining of the anterior chamber and serous covering of the iris are chiefly affected. A more extensive and considerable dulness is present, and copious fibrinous effusion rapidly ensues. The entire pupillary margin soon becomes fixed, and even the whole area of the pupil may be overspread with a white or yellowish effusion. The iris is not partially discoloured in rusty-looking spots, as in the syphilitic form, but becomes uniformly changed to a greenish or yellowish colour. If there is tumefaction, it is also general. In the one disease the serous coverings of the iris are especially affected; in the other, its parenchymatous structure.

The tuberculated and discoloured condition of the iris have been erroneously attributed to depositions of lymph on the free surface of the iris ; but, if the eye be closely and repeatedly examined, the tumefaction will be found to arise from the swollen state of the membrane itself, caused by interstical deposition. The reddish colour is produced by the ramification of vessels, containing red blood, in the aqueous membrane over the inflamed points. The dilatation of these minute vessels must reach a certain point before this cause of the red colour can be detected.

"In moderately severe cases this soon takes place; and, if then, the eye be inspected closely in a good light, and with the assistance of a powerful lens (the cornea and aqueous membrane being clear, and photophobia not great) sometimes only one or two, but occasionally a complete net-work of vessels become manifest, ramifying over the swollen parts of the iris, and evidently imparting to them the rusty red colour which they exhibit. The appearances I now describe may be detected in so large a proportion of cases where this dusky colour is developed, that I cannot doubt that the same hue arises from the same