wards the wind before raising the protection which has been placed over the foot-prints. Then follow the operations necessary to solidify the fugitive impressions.

He should have at his disposal a certain quantity of stearic acid (stearine candles), pulverised chemically-which may be done by dissolving the stearic acid in its own weight of hot rectified spirits,-pouring the acid so dissolved into a large quantity of cold water, which should be stirred with a spatula,-collecting upon a cloth, expressing, and placing it on sheets of paper to be dried by the air. We thus obtain the acid in the state of an impalpable powder.

The experimenter should procure a fragment of thin plate iron, a little larger in size than the impression it is wished to solidfy; he must then turn up the edges of it, and pierce them at different points with holes to facilitate the passage of air, he afterwards places the sheet of iron upon a wire grating in such a way that the bars of the grating shall be about the distance of half an inch from the impression; a few pieces of brick will serve to fix the grating at this distance. The sheet of iron must then be covered with burning charcoal; the iron becomes heated, afterwards becomes red, and by radiation heats the impression. Iron wires may be fixed at the corners of the sheet of iron, so as to raise the temporary furnace at pleasure, or replace it on the grating.

The impression thus heated to a temperature above 2120, about three ounces of the pulverised stearic acid are to be placed on a close-meshed hair-sieve and then sifted on the impression. The acid falls like a powdering of snow, so light in weight that it cannot alter the impression, however faint it may be; it scarcely has reached the ground when it melts and is absorbed by the earth; it may be thrown on until the soil becomes cold enough not to melt the stearic acid further. An excess of this may still be allowed to fall, which excess may be made to melt by bringing afresh the red hot plate of iron over the footprint.

The operation is then completed, and the ground is left to cool perfectly. The time of cooling varies; but it is better to err on the side of excess, that there may be no risk of destroying the impression. The operation will be accomplished more speedily in winter than in summer. If the ground is very light, consisting of sand, dust, or ashes, it will be sufficient to lift the cast with the hands, by the assistance of a spatula passed under the foot-print. It is then placed with care on a linen cloth folded several times, the edges of which are slightly elevated by means of little fragments of wood or stone, in order to form a sort of basin, of which the stearic mould of the foot-print is the bottom, and thin clean plaster of Paris is then poured into this basin to a uniform depth of about an inch. When the plaster becomes solid, the impression is hard enough to be packed in a box between two layers of cotton wadding.

If the ground is more firm, a small circular ditch is dug with care round the footprint, the sides being stiffened with a little plaster, and undermined from below, so as to lift it without injury; this being detached, its bulk is reduced by paring with a knife, and the operation is finished with a coating of plaster as before.

If the foot-print should be upon ground which is muddy or marshy, it would be necessary, before heating the foot-print, to form a circular ditch, and to fill it with dry plaster, which would absorb part of the moisture in becoming solid; it should then be scooped out from below, and the whole lifted, that it may be carried to dry in the shade; it will in this way harden without cracking. It is only after two or three days of drying that the operation with stearic acid can be attempted.

It is easy to see that this process can be applied, with some variation, to all cases of foot-prints upon the ground; and that, upon inspection, the procedure above described may be modified according to circumstances. A hot smoothing iron, a dish cover, or a portable oven, may be substituted for the plate of sheet iron.

These experiments were repeated at a public meeting in the amphitheatre of the Naval Medical School of Toulon, in presence of the president of the civil authorities, and professors; they succeeded so as completely to satisfy all present.

One only objection has been suggested, "How can foot-prints on snow be taken off?" The above process is not applicable to this case. After the next winter, the author will publish a process by which he hopes to be able to solve this difficulty.-Journal de Pharmacie, January 1851.

Part Fifth.

MEDICAL NEWS.

EDINBURGH MEDICO-CHIRURGICAL SOCIETY.

MEETING IV.-February 19, 1851.-Dr BEGBIE, President, in the Chair.

PUBLICATION OF SOCIETY'S PROCEEDINGS.

After the minutes were read, Dr Richard Mackenzie stated, that an erroneous account of the proceedings of the Society had been recently published, in which the facts of the case read by him before the Society, on the 19th January, had been misrepresented. He begged to ask the president, whether the Society could take any steps in this matter?

The President explained, that a subject of this nature must be considered by the Council before being formally brought under the notice of the Society. The minutes were then approved of.

Professor Miller narrated a case of perineal section, which he would have noticed at last meeting, had he not been absent. The operation had been performed according to the old method, without a director, the stricture being impermeable. The patient died, on the 19th day, of pyæmia.

Professor Miller begged permission of the Society to take this opportunity of enlarging somewhat on the subject of perineal section, on account of stricture; and sought to establish, among others, the following conclusions :-That all strictures are not permeable to the catheter or bougie. That the great majority of strictures which are permeable to these instruments are capable of being cured by them safely and satisfactorily, without the use of the knife. That these instruments are neither so insufficient nor so injurious as some authorities have represented. That certain permeable strictures exist, peculiar in resistance or irritability, in which perineal section is advisable; but that such cases are comparatively few. That in them the operation practised by Mr Syme, with a grooved director, is preferable to the old method without a guide through the strictured part. That certain strictures exist-still fewer than the precedingwhich, being truly impermeable, are amenable only to the old method of operating. That such operation is not so difficult, uncertain, or dangerous, as has been sometimes alleged. That all forms of perineal section are not devoid of risk, and ought not to be performed, unless under the pressure of absolute necessity. That any such operation is not to be expected to be alone capable of permanently curing stricture; but that in almost all cases the subsequent use of the bougies will be required to secure a sufficient and permanent dilatation.

Dr Dunsmure agreed with Mr Miller in thinking, that the operation recommended by Mr Syme was a most useful one in those cases in which a tight car

tilaginous stricture existed, and that the great use of the perineal section was to give the surgeon a start, as it were, in the treatment. He was of opinion, that cases did occur in which it was almost impossible, from the irritability of the urethra, to conduct the treatment by dilatation alone to a satisfactory termination. That although he advocated the perineal section in bad cases of stricture, yet he believed that the majority of the cases of urethral contraction could be easily and rapidly cured by dilatation, and that consequently the perineal section would be required comparatively seldom. Three cases had been published by Dr D., in the "Monthly Journal of Medical Science" for November 1850, in which the perineal section had been had recourse to. In the first of these, although the urethra had been opened into, yet the operation as recommended by Mr Syme could not be performed, owing to the stricture extending from fully an inch anterior to the scrotum to the middle of the membranous portion of the urethra, -so that the results of that case could prove nothing; but he thought it right that he should now mention what he knew of the third case. When the patient left the hospital, No. 13 went easily through the stricture; but at his last visit he was only able to pass at first No. 10,-11, 12, and 13 being, however, introduced immediately after; and he (Dr D.) had no doubt, from the tightness with which the bougie was grasped, that, if instruments were not passed, the stricture would ere long become as bad as it was before the operation. Judging, then, from the slight experience he had had from this case, he was inclined to think that instruments would be required to be inserted from time to time after division of stricture by perineal section; but that, notwithstanding, he believed Mr Syme had conferred a great boon upon the profession by showing them a means of treating very bad strictures, and especially those with an irritable state of the urethra, such as one of those alluded to in the course of Mr Miller's communication.

Dr Mackenzie remarked, that in estimating the danger attending the division of the stricture on a grooved director, the consequences of the old operation should be kept entirely out of view. The two operations were essentially different. In the operation proposed by Mr Syme, the limits of the part requiring division were distinctly defined, and the extent of the induration was felt by the finger, when the urethra was exposed by external incision. The point of the knife was made to enter the groove in the instrument immediately behind the induration, and pushed forwards, till the gristly texture constituting the stricture was fairly divided. The urethra was thus divided in the mesial line, and no more was cut than the contracted portion. In the old operation, on the contrary, the knife was plunged into the dilated part of the canal behind the stricture, and was carried forwards as nearly in the course of the urethra as the operator could guess, till it met the point of a catheter introduced down to the seat of stricture. In addition to the incision being thus a more extensive one, there was no certainty as to the parts which were divided, as to the urethra being opened in the mesial line, or even as to the constricted part of the canal being laid open at all. A passage was certainly established, by which the catheter could be introduced into the bladder, but a very different one from that formed by cutting on a grooved instrument passed through the stricture. Dr M. thought, that the term "impermeable stricture" could not properly be applied with so wide a signification as that given to it by Mr Miller; that cases in which part of the urethra had been obliterated, as the result of contusions or lacerations of the perineum, could not properly be included in the term "stricture of the urethra ;" and that the term "impermeable stricture," if used at all, should only be applied to cases of narrowing of a part of the canal, in which the surgeon was foiled in his attempts to pass an instrument. In detailing the consequences of the different modes of treatment of stricture, Mr Miller had made no mention of the serious, and even fatal, consequences which occasionally ensued, from the introduction of bougies, in cases of old-standing and irritable stricture. The occurrence of severe constitutional irritation following the use of bougies, in such cases, appeared to Dr M. to be one of the strongest arguments in favour of the operation proposed by Mr Syme. Dr M. believed, that when the operation of division of the stricture

on a grooved director had been fairly tried, it would be generally acknowledged to be an important improvement in the treatment of the disease, although he thought that the class of cases requiring such a proceeding would be found to be more limited than at first contemplated by Mr Syme.

Professor Miller replied, that he had endeavoured to draw the distinction between the "old operation" and Mr Syme's as broadly as possible, both as to the mode of performance, and the cases to which they were applicable. He had carefully avoided confounding the two in any way. One of his objects had been, not to put the old operation on a par with the new, but to show, that some cases might be expected to occur to which the new operation was not applicable, and in which the old might and should be performed, the more especially, as the dangers and difficulties of the latter seemed to him to be certainly over-stated by the out-and-out advocates of the former procedure. He had also, he thought, made out the fact incontestably, that "impermeable strictures" do occur. But, certainly, Dr Mackenzie had suggested one way of avoiding adhesion to that fact-viz., by change of nomenclature-calling changes in the urethra, when it remains permeable, strictures, and when there is no passage for the urine, obliterations. In most of the cases which Professor M. had adduced as samples of "impermeable stricture," there was no true obliteration of the urethra; and in one, at least, there was no complication with fistula or external injury. Professor M. had alluded, as fully as time would allow, to the use of the bougie; but mainly to defend it from the imputation of what seemed to him undeserved discredit. There was a risk attendant on its use, no doubt, in bad cases; but surely neither greater, nor yet so great, as the "ordinary risks" that attend on perineal section, even of the best kind. Dr Mackenzie had mentioned a case of his (Dr M'K.'s) own, in which the patient had died after the introduction of the bougie, and apparently in consequence of that operation. This proved nothing but an instance of extreme constitutional irritation,-unfortunately, not uncommon. And surely Dr Mackenzie would not say, that the same man, under the same circumstances, would have had a better chance of living, if, in addition to the bougie having been introduced, perineal section had also been performed. Professor Miller begged it to be expressly understood, that he did not appear as an opponent of Mr Syme's operation. On the contrary, he believed it to be an excellent operation, and preferable to all others in certain cases. But, at the same time, he was bound to believe that such cases were very few; and that, at present, there was a risk of this really good operation being put to disadvantage, by a natural tendency in its zealous advocates to impart to it a too wide and unqualified application.

MEDICAL REPORT OF THE EDINBURGH EYE INFIRMARY [INSTITUTED IN 1834] FOR THE YEAR 1850, WITH TABULAR VIEW OF THE CASES. BY ROBERT HAMILTON, M.D., F.R.S.E., F.R.C.S., AND BENJAMIN BELL, ESQ., F.R.C.S.

The experience of each passing day must convince every intelligent practitioner that the healing art, like most others, is a progressive one. This observation, clear beyond dispute, concerning the sciences upon which medicine and surgery are based, and especially in relation to the knowledge which the microscope is revealing, is applicable to almost every branch of professional pursuit, so that the medical man who would neglect this important truth, and disregard these rapidly accumulating discoveries, is speedily arrested, like a stranded bark, whilst others, pursuing a different course, soon leave him far behind.

No department of our science presents perhaps more striking and palpable demonstrations of this important fact than ophthalmic surgery; and the slight notice we now proceed to give of the contents of the accompanying table1 will

1 For which we are indebted to our excellent clerk, Mr Robertson.

NEW SERIES.-NO. XVI. APRIL 1851.

3 с

afford many illustrations thereof. Much has been done within the last few years towards the elucidation of the delicate structures of the different parts of the eye, investigations which must be familiar to many of our auditors, and among which the recent researches of Professors Todd and Bowman are perhaps the most important.1

The prefixed table brings under review more than fifty of the different diseases to which the eye is liable, in numbers varying from one or two only, to several scores; and were we to bestow upon each of the subjects two or three sentences only, our Report would become unreasonably long; hence we must make but a scanty selection, and must strictly confine ourselves within very moderate, not to say narrow, limits.

THE CORNEA.-The large proportional number of cases of blindness which arise from the diseases of the cornea, confer on the disorders of this membrane an importance which cannot readily be overrated. The researches of the gentlemen just named, and of others, seem to have established that the horizontal layers, of which the cornea is composed, and which are somewhat moveable upon each other, amount in number to about sixty. Of these two are distinguished by being especially elastic in their structure, the one on the anterior portion of the cornea proper, upon which again is immediately superimposed, and quite superficial, the conjunctival epithelium; and the other, the posterior elastic lamina, with which we have been long familiar as the membrane of Decemet, and which, like the anterior one, is also lined, of course posteriorly, with an epithelial pavement. These peculiar lamina are sheets of homogenous membrane, very much resembling the capsule of the lens, being perfectly transparent and glossy, firm, resisting, uniform, and without appearance of internal structure.

1 See Physiological Anatomy and Physiology of Man. By Dr Todd and William Bowman, F.R.S. Also, Lectures on the Parts Concerned in the Operations of the Eye, &c. By William Bowman, London. 1849.