is no probability, as before stated, that the smallpox had part in exciting the suppuration, since this must have been long antecedent to the operation of the variolous poison. This and the two following cases are instances of a similar association of chronic disease of the chest with cerebral abscess.

The doctrine of final causes, so freely quoted by modern pathologists in explanation of morbid phenomena, receives a shock from the facts of cerebral abscess. Whatever "efforts of nature" the course of abscess elsewhere may seem to show, we can recognise in its course in the brain but mechanical principles, according to which the yielding is in the direction of least resistance, and the pus thereby slowly makes its way towards the cavity of the lateral ventricles irrespective of the well-being of the individual.

The sudden accession of delirium was probably brought on in this case by such an accident. In a similar case, recorded by Abercrombie, a man, æt. 43, had for ten days complained of headache, but was still able to follow his employment. Early one morning he was seized with palsy of the left side of the face, and became unmanageable. The pupils were contracted and the eyes in perpetual motion. He made the most powerful resistance against being bled. He died on the fourth day. Three encysted abscesses were found in the brain, the largest of which had burst into the lateral ventricle.

CASE 13 (37).-Pleuro-pneumonia of the base of right lung, followed by fetid expectoration; death after three years from encysted abscess in the brain; cavity in lower lobe of right lung, with several bronchial tubes opening into it.

A gentleman, æt. 34, tall and well proportioned, with light hair and fair complexion, was in good health until December, 1853, when, from exposure to cold, he had an attack of acute pleuro-pneumonia of the lower lobe of the right lung. In March following the symptoms returned, and he began to expectorate muco-purulent fluid of a peculiar earthy fetid odour. In a few weeks he was able to go to business, but was never again robust. The expectoration continued purulent and fetid. Exacerbations of the local chestsymptoms occurred from time to time, and were generally attended with slight hæmoptysis.

In this way he went on until March, 1856, when he had a sudden seizure, lasting for nearly two hours. The symptoms were vertigo, faintness, and loss of power on the right side; he was not unconscious. The day following

he was at his business as usual, but ever after he would at times complain of a tired feeling in the head, and was easily fatigued. Singing at church and other loud noises distressed him. With these exceptions, however, he appeared in his usual health, and continued to perform active duties; and though I often saw him for the chest affection, he never complained of anything in the head. November 15th, about two o'clock, he was surprised by a sudden and violent chronic convulsion of the right arm, lasting for several minutes. It was so severe as to oblige him to support himself by holding the table with the other hand. He felt quite well at the time, and when the muscular action subsided went on with his duties as before. He left the warehouse at four o'clock, and was walking to the omnibus, when the right arm was similarly affected a second time for a minute or two. He still felt quite well, and took his place in the omnibus, but had not proceeded far before the movements returned a third time, now affecting slightly the muscles of the face and of the leg on the same side. After lasting as before, but a few minutes, they again left him. When I saw him at six o'clock he appeared quite well. The voluntary movements were everywhere perfect; vision and pupils natural; no headache nor trace of mental disturbance, and, with the exception of slight and transient vertigo at the time of the third return of the movements, there had been no symptom referable to the brain. He assured me he felt quite himself, and on my requesting him to walk round the room and examine the pictures and engravings on the walls, he asserted that he saw them quite naturally. He continued well until noon of the following day (November 16th), when the convulsions returned a fourth time, beginning in the same way with clonic spasms of the arm and face, on the right side, without loss of consciousness, but quickly assuming the character of a severe epileptic seizure, with insensibility. After two hours he recovered, and the next day (the 17th) wrote to his sister, and complained only of weakness. On the 18th he had another convulsion, with insensibility, followed by partial paralysis of the right arm and leg. On the 20th he slept nearly the whole day; when awake he was quite himself, except the inability to move the right arm and leg freely. Up to this time he had no headache, and no delirium. On the 21st and 22nd he continued in the same state; pulse 80; skin cool; no heat of head; perfect clearness of intellect when fully awake; slight headache towards evening; constipation. On the 24th the arm and leg were more numb and powerless; about noon the whole side was convulsed, and he became insensible. The convulsions continued, with only short intervals of quiet, until 4 p.m. After consciousness returned he remained speechless for many hours. On the 25th and 26th he was much troubled by the almost constant recurrence of the clonic convulsion of the right side, including the face, but without insensibility. After the application of leeches, a blister, and free evacuation from the bowels, he was much relieved, and slept tranquilly. On the 27th he complained of a "dead pain" in the head; there was still no febrile heat; he raised the right arm with more power; pulse 80. On the 29th the arm and leg were quite paralysed ; the muscles flaccid; sensation not much diminished. By this time he had greatly emaciated; when asked if he had pain in the head, he replied slowly "I ought hardly to say pain," and afterwards added, with a smile, that he

was comfortable. The administration of an enema brought on convulsion without insensibility. On December 3rd there was great cerebral depression; he used words incoherently, asking for one thing when he meant another. There had been no convulsive movements for two days, but now and then he seemed to faint for a time; the left hand was constantly pressed to the left side of the head; the right arm and leg were perfectly paralysed, and the muscles of the face on the same side partially so; pulse 80; tongue protruded straight. On the 4th he uttered a few sentences very slowly and interruptedly, but lay for the most part in a half comatose state; took food readily. During the 4th, 5th, and 6th, he lay perfectly quiet, occasionally breathing with a little stertor, but generally so calmly that it was difficult to say whether he breathed or not; could be roused, and understood what was said to him; expressed by signs his desire to have food and the like. On the 7th the urine passed from him involuntarily, though he retained his consciousness, and once smiled faintly when his sister was near him. From his movements it was evident he suffered a good deal of pain in the head. He could not understand questions, but recognised signs; pulse 56; respiration 20; pupils equal, rather less contracted than in sleep; abdomen collapsed; several rigors, followed by spasmodic extension of the whole body. On the 8th was unable to swallow; towards evening very severe convulsions came on, and lasted several hours, when he died exhausted.

Post-mortem examination.-The integuments of the head and calvaria healthy. In the posterior lobe of the left hemisphere of the brain, on a level with the corpus callosum, there was an encysted abscess, containing two ounces of mucoid, greenish, fetid pus. The cyst was bounded externally by a thin layer of greenish brain-substance, the membranes over it were not inflamed. The wall of the cyst was about one tenth of an inch thick; it was vascular. The brain-tissue around was softened from inflammatory œdema. Slight increase of fluid in the lateral ventricles. No disease of the temporal or of the other bones at the base of the cranium. Firm pleuritic adhesions over the lower lobe of the right lung, and an irregular cavity, as large as a pullet's egg, in the pulmonary tissue. The lining membrane of this cavity was smooth and transparent, and on the proximal side perforated by several bronchial tubes. The tissue around was indurated. No trace of tubercle in any of the tissues. Abdominal viscera healthy.

Remarks. The sudden seizure in March, though so transient that it caused no alarm, was probably indicative of the commencement of the suppurative process in the brain, which afterward pursued, during eight months, an entirely

latent course.

The order of the symptoms in the final attack, was characteristic of the onset and extension of the inflammation around the old cyst of the abscess. Clonic spasm of the right arm as an isolated symptom, without any other disturbance of the nervous system, was the opening phenomenon. The day

following the convulsions became epileptic. On the fourth day, after a repetition of such convulsions, the right side was left partially paralysed. The hemiplegia then gradually became complete, and the patient became drowsy and indifferent, and at length comatose. These symptoms, associated with the chronic disease in the lower lobe of the right lung, were the basis of a correct diagnosis.

CASE 14 (38).-Encysted abscess in posterior lobe of left cerebral hemisphere; heart drawn over to right side of chest ; pleuritic adhesions; external fistulous opening, and dilated bronchial tubes on the same side. J. H—, æt. 23, a policeman, who had been in Guy's Hospital a year before for pleurisy, was again admitted March 23rd, 1853. His symptoms were considered obscure. It was suspected that he might be labouring under chronic hydrocephalus. There was mental confusion and loss of memory. No paralysis. He was sensible until his death, which took place unexpectedly April 28th. The account he gave of his illness was, that six weeks before admission, whilst on duty, he had a sudden seizure with partial loss of consciousness, and the same day a second seizure. After a month he had a third seizure. From the time of the first attack he had headache and vomiting.

Post-mortem examination.-No disease of the cranial bones. Membranes of the brain healthy. A large abscess in the substance of the white matter of the posterior lobe of the left hemisphere, not implicating the thalamus opticus. The walls of the abscess were remarkably thick, and in many parts mottled with tortuous capillary veins. The whole cyst was easily enucleated from the surrounding cerebral substance, which was softened and of an opaque white. The walls of the cyst could be divided into three layers; the external layer was finely fibrous and rather loose, and composed of a cellular web, the remains of softened nervous tissue; the middle layer was dense and translucent; it was formed of fine, rather flattened fusiform fibres, with elongated nuclei; the inner layer, or so-called pyogenetic membrane, was opaque and brittle; it consisted of an adherent layer of nuclei and exudation cells, many of which were undergoing granular degeneration. The pus amounted to about two ounces. It was clotted and mucoid, and decidedly alkaline. It contained opaque granules and fibrinous shreds undergoing earthy infiltration. The abscess had burst into the descending cornu of the lateral ventricle. The surface of the corpus striatum and thalamus on the side of the rupture was of a dull colour, but without inflammatory exudation. Right lung universally adherent. The lower portion of the pleura thickened, and in it a fistulous canal opening externally, but not communicating internally with the lung. Pulmonary tissue compressed, the tubes dilated. Heart drawn over to the right side by adhesions of the pericardium to the lung. Left lung partially adherent.

any

Remarks.-There cannot in the nature of the case be symptoms pathognomonic of abscess of the brain. It is often only from the collateral circumstances that we can rightly estimate the nature of the cerebral disorder. In this case the sudden seizure with partial loss of consciousness, if not epileptic, should have caused a suspicion of some local disease in the brain. The same symptom has often been noticed in cases of tumour as well as of abscess. The differential diagnosis would rest upon the absence of pain preceding and following the seizure; the rapid progress of the symptoms, marked by weeks, rather than by months; the character of the cerebral oppression; and the local conditions of the chest. The frequent absence of rigors in cerebral suppuration has been already noticed. Although the contents of the abscess were undergoing the earthy change there was a gradual extension towards the lateral ventricles.

CASE 15 (39).-Inflammatory cysts, with surrounding solid exudation in anterior part of right hemisphere of brain, probably excited by contre

coup.

William S, æt. 40, a tall, athletic man, of rather free habits, though not a drunkard, by occupation a mill-wright, began to suffer with severe headache in the spring of 1854. The pain was principally across the forehead, and at times so severe, that, to use his own expression, he thought he should go out of his mind. He continued at his work until the end of November, when his memory became impaired; he had transient attacks of unconsciousness, and at other times lost his sight for half an hour or so. He had frequently double vision, and was troubled by dark, irregular forms creeping before him. From this time he had vomiting and constipation, and began to emaciate. January 5th, 1855, he was admitted into Guy's Hospital under the care of Dr. Barlow. His manner was dull, he complained of constant pain in the head, aggravated in paroxysms. There was no paralysis, but his movements were sluggish, and he could not stand long without feeling faint. Vision impaired. Pupils dilated. Urine scanty, depositing phosphates largely when heated. His wife gave an account of a severe fall which he had about Christmas, 1853, by slipping upon the pavement and striking the back of his head. He was stunned at the time, but the effect soon passed off, and the accident was forgotten. He remained in the hospital until the 24th of February. On several occasions he had seizures in which he lost all muscular power; these he called faintings. At the beginning of April he was readmitted into the hospital. He was then totally blind. He could neither walk nor stand, but could move his limbs, though he did so tardily, especially on the left side, and remarked that "they did not feel the right thing." The left seventh nerve was partially