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of lead, which shows, that it contains neither gum nor extract. It is therefore a pure resin.

The resin thus treated with boiling water was dissolved in alcohol. This tincture strongly reddened that of litmus, and had no action on sirup of violets.

Powdered sandarach was digested in alcohol, and boiling water poured into the hot filtered solution, which precipitated the resin. The filtered liquid grew turbid on cooling; it had the strong smell of resin of sandarach; its taste was bitter; and its action on the tincture of litmus was so weak, that it could not be supposed to contain a free acid.

2. Mastic. This substance exhibits nearly the same phenomena as the preceding; but the resin concretes into a mass in boiling, like turpentine. The water has a bitter taste, and has no action either on litmus or sirup of violets. The resin, on the contrary, strongly reddens tincture of litmus.

3. Olibanum forms with hot water a thick pap, which is separated from the liquid with difficulty even by filtration. This water has a blackish brown colour, is not precipitated by acetate of lead, and does not alter the colour of litmus; but alcohol throws down a copious precipitate from it, which proves, that this substance is composed of gum and resin.

The alcoholic tincture strongly reddens that of litmus.

If the resins that have most action on the colour of litmus be heated with all due precautions on a sand bath, no acid sublimes.

Treated with lime, according to Scheele's process, no calcareous benzoates are formed.

4. Lastly, the gum resin ammoniacum, myrrh, elemi, anime, galbanum, tacamahacca, resin of jalap, both prepared by ourselves and that of the shops, Venice turpentine, oil of turpentine, and several other resinous and gumresinous substances, afforded the same results as those obtained from scammony, sandarach, and olibanum. From these facts it appears still difficult to solve the question, whether the reddening of litmus by resins be owing to the presence of an acid in them.

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If acids alone had the property of reddening vegetable blues we should not hesitate to admit their existence in resins, though not yet otherwise demonstrated by experiment. As to the infusion of violets not being reddened by resins, this property occurs in the sublimed acid of benzoin, which strongly reddens infusion of litmus, but does not alter the colour of violets. Has this acid, notwithstanding its solu bility in water, some analogy to resins? On this we refrain from giving a decided opinion; yet we are inclined to believe, that this substance is a compound of a vegetable acid and a

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small portion of resin, to which perhaps its solidity is owing. Finally, as all the vegetable acids are soluble in water, it is difficult to ascribe to an acid this property in resins of reddening litmus. It appears more proper therefore, to consider the reddening of litmus as a character of resins, till fresh experiments have proved the contrary.

1

"CRITICAL ANALYSIS

OF

RECENT PUBLICATION.S

IN THE

DIFFERENT BRANCHES OF PHYSIC, SURGERY, AND MEDICAL PHILOSOPHY,

Transactions of the Medical Society of London.
(Concluded from p. 63 of the Journal.)

MR. WARE, one of the Vice Presidents, has favoured the Society with an interesting account of some diseases of the eye, which forms the subject of the 6th article. The first of these he styles staphyloma, this term has been used to designate the protrusion of a part of the iris through a wound or ulcer of the cornea; but Mr. Ware uses the term to denote a projecting opaque cornea.

"It has been disputed by authors (he remarks, p. 116) whether the projection of the opaque cornea in the staphyloma, is occasioned by thickening of this tunic, or by a morbid accumulation of aqueous humour behind it. I believe, in general, both these circumstances combine to produce the disorder; the cornea becoming not only opaque, but softer and thicker than in its natural texture, and, in consequence of this, the aqueous humour behind the cornea pushes it forward, and thus enlarges the anterior chamber of this humour. I have sometimes seen the whole cornea sloughed off during an acute purulent ophthalmy, and a white opaque substance gradually effused from the ulcerated surface, sufficient to form a complete cover to the iris; after which this opaque body has gradually projected in a conical shape, until at lengthit has become so prominent as to hinder the eyelids from closing over it. I have at other times seen the projecting cornea partly opaque, and partly transparent: the pupils being distinctly visible through the transparent part, but the power of vision wholly destroyed. Sometimes the circumference of the opaque cornea projects, its central part appearing depressed, and resembling the bottom of a plate or dish; and sometimes near to the center of opacity, in the last case mentioned, there is an irregular black appearance, which a cursory ob erver might mistake for a pupil. No part of this aperture, however, is perceptible on a careful inspection, and the eye of course is deprived of all useful vision. (No. 144.)

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Mr. Ware

Mr. Ware next considers the means of affording relief. When the projection of the opaque cornea can be covered by the eyelids, without painfully stretching thein, if the surface of the cornea continue regular, and the sight of the other eye perfect, no inconvenience, except the unseemly appearance, is produced. This may be remedied by wearing spectacles containing plain window glass in the ring opposite the sound eye, and glass that is ground in a slight degree opaque, in the ring opposite the affected eye. In some cases it is necessary to sink the eye. For this purpose caustics and other strong applications have been proposed; but Mr. Ware deems them dangerous and inadequate. The mode of compressing the tumour, he states, is difficult, and he only remembers one case in which it afforded advantage.

The more direct way of affording relief in the staphyloma is by removing the whole of the projecting substance; in consequence of which the humours of the eye are discharged, and the posterior part of its tunics collapse, so as to form a kind of button at the bottom of the orbit. On this button, when the wound is healed, an artificial enamelled eye is capable of resting; by which the uniform appearance of the face may be restored."

Our author proceeds to enquire into the best mode of performing the operation. He objects to the method of passing a double ligature through the tumour, and tying it on each side, as practised by Neister, St. Yves, and others, because it is a painful and indirect mode of accomplishing our object. He thinks Scarpa's method of removing a small portion only of the projecting cornea, and forcing out the crystalline and vitreous humours, is liable to considerable objections, for which, however, we must refer to his paper, and content ourselves with giving Mr. Ware's own mode of operating, which he informs us has uniformly succeeded in a considerable number of cases during a practice of more than thirty years.

The operator is directed to stand behind the patient, who is to be placed on a chair, sufficiently low to allow the operator to carry his hand with ease over the patient's head. A large crooked needle, armed with a strong thread, should then be passed through the opaque projecting cornea, and after separating the needle from the thread, a knot should be tied in the latter, at a small distance from the eye, in order to hinder the thread from slipping. The operator having thus obtained, by means of the thread, a secure hold of the eye, a knife similar to that which is used to divide the cornea in extracting the cataract, or, if this be not at hand, a long sharp-pointed lancet, should be pushed through the sclerotic coat, about a quarter of an inch from its connection with the cornea, and be carried quickly but accurately round the cornea, as nearly parallel to it as can be accomplished. Sometimes, as soon as a puncture is made through the sclerotica, so large a portion of the vitreous humour escapes, as to cause the cornea to become flaccid, in consequence of which the operator may find it difficult to complete the inci

sion round this tunic with either the lancet or the knife, and in this case a curved blunt-pointed scissars will be found useful to finish the operation. The only objection to the use of the scissars is drawn from the additional pain which it is supposed to give; but the duration of the cperation is so short, that the difference between the pain produced by the instruments is scarcely worthy to be named. The hemorrhage that succeeds is seldom considerable; and the less the eye is examined afterwards, the less danger will there be of pain and inflammation. A com press wet with a saturnine lotion should be applied over the eye, and it should be moistened as often as it becomes dry; but no lint or any other application should be put within the lids, since this has been known to give great pain, and in one instance to occasion alarming symptoms. An anodyne should be given after the operation, of greater or less strength according to the age of the patient; but it is seldom necessary to repeat this medicine, since the patient has usually more sound and quiet sleep after the operation than he had for a long time previous to its performance. At the end of about a fortnight, that part of the sclerotica which remained in the orbit will be found to have collapsed, and sometimes a small fungous substance will then protrude through the wound. This in the course of time would subside of itself, but, as the delay may be irksome, the fungus may be easily removed, and with very little pain, by nipping it off with a pair of sharp scissars. The fungus is usually smaller in its neck where it joins the sclerotica than in its top; in consequence of which its removal is effected with very little difficulty; and though it sometimes reappears, it may be nipped off again and again, until at length the wound will completely close, the inflammation cease, and the orbit become fit to receive an artificial eye. This, however, ought not to be introduced until the inflammation be perfectly removed, and when such an eye is used, it is adviseable to withdraw it every night and replace it in the morning, which may be effected with ease by the patient himself after a short experience. P. 127.

Hydropthalmia, to which Mr. Ware next calls our attention, is an enlargement of the whole eye, produced by an increase of the vitreous as well as of the aqueous humour, which causes the eye to occupy an undue portion of the orbit, and occasions pain when the eye-lids are closed over it. Children are sometimes born with the cornea large, prominent, and opaque; these, in general, are removed as the child grows older, by what Mr. Ware terms," the vis nature medicatrix," without any particular remedy being employed, But when the enlargement is not confined to the cornea, and extends to the sclerotica, and the eyelids cannot be closed without difficulty; the patient being at the same time blind, and unable to sleep without opiates, it becomes necessary to devise some means of affording ease, and obviating de formity; for the prospect of restoring sight is lost. For th's purpose we are recommended to perform the operation for diminishing the eye, as directed in cases of staphyloma.

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"Before an operation of so much importance be performed, it is, however, essentially requisite to ascertain that the disease consists solely in

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an enlargement of the different parts of the cye; and that it is not produced by the formation of purulent matter within the eye; by a morbid alteration in the structure of either its coats or humours; nor by the undue accumulation of adeps, or of any other substance, behind this organ." P. 134.

Some cases illustrative of Mr. Ware's mode of discrimi.. nating these affections, and his method of treatment are related. For his account of Carcinoma, we must refer to the volume itself, having already advanced too far beyond our limits.

The 7th article, by Mr. Burns, of Glasgow, is a case of suppuration of the liver, with appearances resembling Ascites, which terminated favourably. A girl aged twelve, on the 20th of June, 1798, complained of sickness, pain about the upper part of the abdomen, shooting to the right shoul der, heat, and frequency of pulse. An emetic was given; the pained parts were rubbed with some embrocation, and saline draughts were prescribed. The pain continuing, on the 10th of July, a blister was applied over the lower ribs, and was repeated on the 15th without much advantage. For some days previous to this, the belly had been fuller than usual; and the swelling having increased, diuretics were ordered. Mr. Burns saw her, for the first time, on the 19th of July, and says,

"I found the right hypochondrium tumid and painful to the touch, especially near the stomach, and toward the lower part. She had pain in the right shoulder, and could not lie with ease except on her back, or inclining to the right side. The tongue was furred, the tunica adnata of the eye was of a yellowish colour; the urine was high coloured, and deposited a copious pink coloured sediment. The belly was bound, and the stools, when procured, were of a light colour. The appetite was much impaired, and she had frequent fits of sickness and retching. The pulse was 115, sometimes 120; the body emaciated, and the skin wet with perspiration, whilst a hectic blush pervaded the cheek. The belly was considerably swollen, and a fluctuation could be discovered. The tumor had not so diffused an appearance as is observed in Ascites, but was more rounded, as if a large globe had been placed below the umbilicus.

"She was now put on a course of mercury which was continued three weeks, so as to keep the mouth somewhat sore. During this time the symptoms of hepatic inflammation went off, she slept better and felt easier; but the hectic symptoms continued, and, although the diuretics had not been discontinued, the belly increased in size."

On the 12th of September, she was tapped in the usual way, and about six pounds of well conditioned pus were drawn off. After this she soon got entirely well. In the middle of October the belly again swelled, but not to half its former size; the umbilicus protruded and inflamed a poultice was applied, and in a few days the skin burst, and nearl

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