than on right side. "Bruit de pot félé" elicited by striking smartly the second intercostal space. The treatment adopted in this case, in addition to attention. to special symptoms, has been the administration of half an ounce of cod-liver oil, at first twice, subsequently three times a day. The improvement in this patient's general health is very decided, and you would not suspect from her appearance the existence of any serious disease. I call your attention to her case, not only as an example of the cracked-pipkin sound, but also as an encouragement to persevering treatment, even in seemingly hopeless cases; for the evidence of large cavities in each side of the lungs is conclusive.

You recollect the explanation formerly given of the cause of the cracked-metal sound-namely, the escape of air into a large bronchial tube from a considerable cavity, with yielding walls so near to the surface of the chest as readily to receive an impulse from the stroke made in percussion. The production of a similar sound by any other cause is so rare that I shall not now embarrass you by the discussion of that subject. Since last Wednesday, a poor woman, J. B—, has died in the hospital, in whom, during the whole period of her stay, this particular sound was remarkably distinct on making percussion under the left clavicle. I now exhibit the apex of the lung. You observe that it contains a cavity large enough to admit a melon, and that the pulmonary substance is at one part so much destroyed, that a portion of the cavity is absolutely bounded by the pulmonary pleura. Two or three bronchial tubes are seen opening into the cavity, one of which enters abruptly, and communicates directly

with the left bronchus. Thus you perceive that all the conditions above described as contributing to the production of the cracked-metal sound, are distinctly fulfilled. There was another circumstance of considerable interest, and, indeed, of rarity, in this patient's case :namely, the occurrence of gangrene of the hand. On December the 15th, about a month before her death, she complained of numbness, followed by pain of the left hand, fingers, and arm; and these parts, on the 17th, were observed to be slightly livid; this lividity extended to within an inch of the wrist in front, and an inch and a half on the dorsal surface of the hand. The cuticle was raised into a vesicle on the dorsal surface of the first phalanx of the index finger. No sensation evinced when tried with a pin within an inch above the wrist. Temperature of the left dorsum, 76°; of the right, 931. Temperature of forearm also diminished, and superficial veins distended. No pulsation to be felt in the radial artery; pulse, 118; bowels confined. She was directed to have a drachm of castor-oil immediately, and repeated when necessary; a grain of watery extract of opium at night; and every four hours an ounce of the following mixture-Half a drachm of sesquicarbonate of ammonia; three fluid drachms of spirit of sulphuric ether; five drachms of syrup; five ounces of decoction of Peruvian bark. Hand and forearm to be enveloped in cotton wool.

On the 21st, the lividity was in part replaced by redness, and sensibility had extended a little below the wrist. The pulse, which on the 18th had been 180, was reduced to 104. The watery extract of opium had been given for three days every six hours. To have six grains of chlorate of potash, with an ounce of decoction

of bark, and a drachm of syrup, every four hours, and to continue the opium every four hours.

22nd.-Passed a restless night, dozing from time to time for ten minutes; pulse, 94; temperature of left dorsum, 7210.

23rd.-Pulse, 92; temperature of left dorsum, 66°; of right, 81°; of inside of mouth, 94°; bowels confined; no pulsation below the subclavian artery. Morphia, in quarter-grain doses, substituted for the watery extract of opium, and castor-oil repeated. At night a turpentine enema was administered with good effect.

24th.-Pulse, 98; tongue dry; lividity partly superseded by redness; hand and arm very painful, especially when the cotton wool is temporarily removed. An additional allowance of brandy, wine, and eggs; a grain of opium at bed-time.

25th.-Pulse, 104; commencing discoloration of forearm; appetite improved. Two grains of opium at bed-time.

26th.-Passed a better night, but lividity extending on the dorsum; no sensibility short of an inch and a half above the wrist on the anterior surface, and three inches on the posterior surface of the forearm.

28th.-Pulse, 98; arm more painful. Ten drops of sedative solution of opium every third hour, and half a drachm at bed-time gave considerable relief; but she continued gradually losing strength, notwithstanding the free use of stimulants.

On the 8th of January, the temperature of the left dorsum was 70°, and vesication had taken place on the anterior surface; forearm semiflexed; hand fixed in a position midway between pronation and supination ; discoloration half way up the arm in front; three

inches and a half behind; pulse, 116; expectoration very difficult. The quantity of chlorate of potash was increased, and the opiates and stimulants continued.

On the 10th, diarrhoea; a rapid weak pulse; legs and feet increasingly coedematous.

Died on the 11th, at half-past two, A.M.

It was pretty evident that some cause had interfered with the circulation in the left subclavian artery. The port-mortem examination disclosed the nature of the obstruction. The arch of the aorta, and the arterial branches, as far as the palmar-arch, were removed by Mr. Hunt for examination. A coagulum extended for about three inches along the subclavian artery, occupying nearly the whole calibre of the vessel. It adhered strongly to the aorta near the opening of the vertebral artery, which in this subject arose from the arch between the left carotid and the subclavian, but this coagulum could easily be separated from the subclavian, and was pointed at the distal extremity. The left vertebral artery was narrow at its commencement, and was closely filled with dark-coloured coagulum. Coagula also occupied at their commencement the circumflex, ulnar, radial, and interosseous arteries, beginning an inch or two above their origin, leaving free those parts of the vessels which were most distant from any important branch. The coats of the aorta, for a space of about an inch in diameter at its fore part, were thickened from atheromatous degeneration, which, under the microscope, exhibited fatty deposit in the circular fibres. In the centre of the diseased patch was a softened portion, half the size of a pea, consisting, as reported by Dr. Quain, on a microscopical examination, of aggregated granule cells, fatty particles, and chole

24

COAGULUM IN THE SUBCLAVIAN ARTERY.

strine, and surrounded by calcareous deposit to the extent of two or three lines; and, to a part of the altered structure, the coagulum was so strongly adherent that, when violently pulled, at a scientific society, a portion was left attached to the vessel. The heart was somewhat hypertrophied, but in other respects perfectly healthy. The explanation which some might suggest of the origin of the coagulation-viz., the diseased condition of the aorta-is to me unsatisfactory, and appears to remove the difficulty only a step. As subsidiary circumstances, I cannot help attaching some importance to the peculiar situation of the origin of the vertebral artery, as calculated to disturb the equable current of blood through the aorta; and also to the condition of the orifice of that vessel, which seemed to me narrow beyond what could be accounted for by thickening of the arterial tunics; and it appears to be an illustration, in addition to others which have come under my observation, of an opinion that parts which present anatomical irregularities are prone to become by preference the seats of disease.

Malformation indicates defect in the direction of formative energy, and it is not surprising that such defect should entail susceptibility to diseased action. The nature of the connexion between the diseased condition of a portion of the aorta and the gangrene of the hand is a fair subject for speculation; but it must not be forgotten, in reference to this inquiry, that examples of extensive and seemingly spontaneous gangrene have occurred without any evidence of arterial disease.

A case described by Mr. Solly,* of extensive gan* Transactions of the Royal Medico-Chirurgical Society, vol. xxiii., p. 237