cerebro-spinal fluid may be present at different times in greatly varying numbers on occasion even practically disappearing. This fact shows the necessity of repeating the puncture, after a sufficient interval, if the first examination fails to yield a positive As has been said, albumin cytologic reaction in a suspected case. is usually present in association with the lymphocytosis, but not always, and does not depend upon it, albumin being sometimes pathologically demonstrable when no cells are to be found.

The principal diseases of the nervous system in which white blood cells occur in the spinal fluid may be summarized thus: Leucocytosis.—Acute congestive or inflammatory processes in the meninges; epidemic cerebro-spinal meningitis; brain abscess. Lymphocytosis.-Dementia paralytica; tabes dorsalis; cerebrospinal lues, including luetic meningitis, myelitis, and meningomyelitis; tubercular meningitis.

In cytodiagnosis we possess a method of examination which often clears up early and positively difficulties in differential diagnosis, which without it, might long persist, to the embarrassment of the clinician and the annoyance of the patient's friends. In cases where the so-named functional psychoses, hysteriform, and neurasthenic states, alcoholic insanities, involutional forms, degenerative types, choreic insanity, the maniaco-depressive and dementia präcox groups come into consideration as differential possibilities, lumbar puncture may yield the most valuable evidence, the conditions named furnishing regularly a negative cytologic reaction. On the other hand, practically every case with Argyll-Robertson pupil presents also a spinal lymphocytosis, the reaction being most constant and most marked in paresis.

In addition to the cases in which the clinical evidence has not seemed sufficient to warrant an early diagnosis of tabes or paresis, and in which lumbar puncture has decided the question, other obscure forms have occasionally been cleared up by this means,

To allow the subsiding of a possible slight reaction due to the irritation of the meninges produced by the needle, ten days should be allowed to elapse before a second tapping is undertaken.

Lymphocytosis has also been observed in cases of herpes zoster, epidemic parotitis, and sciatica. In epilepsy various observers have regularly reported negative results. MERZBACHER, in twelve cases from the Freiburg clinic reported a moderate reaction in 6, and a slight reaction in 2,

negative in 4.

unsuspected conditions revealed, false diagnoses corrected. DUPRE mentions among seven tabetics, all of which showed lymphocytosis, one patient who applied for treatment for persistent diarrhoea, and whose only other symptoms were myosis and loss of the achilles reflex. Lumbar puncture confirmed the diagnosis of tabes. MILIAN refers to the value of cytodiagnosis as a means of distinguishing between headache of specific origin, and that otherwise conditioned. CHAUFFARD and BOIDIN, in several cases of acute infection with marked irritative meningeal symptoms (meningism), demonstrated by means of lumbar puncture the non-involvement of the meninges. Cases of focal hæmorrhage and areas of softening have been recognized by the presence in the spinal fluid of the so-called granule cells, better described as reticulated cells, the phagocytic elements which early make their appearance in a necrotic focus in the central organs. These cells may be found laden with erythrocytes or drops of myelin. In one case of focal necrosis observed by SABRAZES, MURATET, BONNES, a nerve cell, escaped from the breaking-down tissue, had floated out into the cerebro-spinal fluid, and was recovered in the test-tube by lumbar puncture. Another case, cerebral cysticercus, was diagnosed by the occurrence of the organism in the fluid (HARTMANN).

The technique of lumbar puncture for cytodiagnostic purposes, as taught by the French school and followed by the majority of observers, is too well known to require mention. The method has one cardinal defect. It should be possible to study under the microscope the formed elements in the fluid just as in the case of a blood specimen taken intra vitam. Centrifugation makes this impossible, for during the process the elements become deformed and otherwise altered post mortem, and may lose to a greater or less degree their tinctorial capacity. While therefore the cells can be counted and the distinction made between leucocytes and lymphocytes, a satisfactory differential estimation is quite out of the question. The method of best promise for obviating this difficulty is that by which the newly-drawn uncentrifugalised fluid is used. For simple counts ROSENTHAL diluted the fresh fluid one-tenth with a solution of methyl-violet in a Zeiss mélangeur, and enumerated the cells by means of the counting-chamber. In this way he found in fifteen luetic and metaluetic cases an average

of 60 elements per cubic millimeter, while in fifteen normal and functional cases the average number of cells was 0.5 to 2. Accurate differential counts of the elements in the spinal fluid have yet to be undertaken. They must also be made with uncentrifugalised liquid, and will perhaps throw light upon the relation between these elements suspended in the fluid and those which make up the advential exudate in the central tissue itself.

In addition to the intra vitam method, lumbar puncture has a certain diagnostic value as a part of the post mortem examination. Post mortem evidence would, however, depend solely upon the study of the cellular elements contained in the fluid; chemical tests would obviously be untrustworthy. From the cytologic point of view GIANNUZZI reported practically the same results in the examination of the spinal fluid in the cadaver not later than twenty-four hours after death, with the same diagnostic differences, as he obtained during life.

It remains but to mention two or three points concerning the necessary precautions accompanying the operation, its possible consequences and contraindications. In the first place, the operation of withdrawing fluid from the cerebro-spinal canal is by no means an entirely indifferent and innocent procedure, but may be followed by symptoms more or less distressing or alarming, dependent upon the condition of the subject, the technique of operation, and other circumstances. These unpleasant after-possibilities have been disregarded by many authors, notably the French, or have been dismissed with the remark that transitory headache or nausea and vomiting had been observed. Only recently, especially in Germany, following the studies of NISSL in the Heidelberg clinic,' has this side of the question come to receive more attention. Headache of a severe type, nausea and vomiting, persistent backache and nuchaeal pain, utter lassitude, mental hebetude, are common enough after the ambulatory form of operation which cannot be too severely condemned. These symptoms may confine the patient to his bed for days or even weeks,

TO DEVAUX is due the credit of having stimulated interest in the cytologic study of the spinal fluid in Germany. He introduced the technique of WIDAL at Heidelberg (v. Centralblatt für Nervenheilkunde und Psychiatrie, XXVI, No. 161), after which appeared the studies of NISSL,

SCHONBORN and others.

and to obviate or at least mitigate them, he should be placed in bed immediately after the operation, if not already there, and should be kept in a horizontal position with head low for a number of hours, better for the remainder of the day or until any uncomfortable symptoms have subsided. In NISSL's series several normal individuals were included. They were chiefly assistants in the clinic or students who volunteered their services. In these cases the subject merely sat down to be tapped, after which he went about his usual occupation. There followed usually a free interval of from three to five hours during which nothing extraordinary was experienced; then came the headache and other symptoms mentioned, which varied greatly in intensity and duration. During their acme the subject was incapable of the slightest effort, being compelled to remain in a horizontal position at physiologic rest. Under such circumstances it was noted that the giddiness, nausea, pains in back, neck, and head, were often remarkably alleviated, but reappeared in full intensity as soon as the attempt was made to sit up or even to raise the head. The duration of this condition varied in the several cases from a few hours to fifteen days.

A second point concerns the amount of fluid to be abstracted. It is scarcely necessary to say that this should be as small as possible. 3 to 5 cubic centimeters suffice for the usual cytologic and chemical tests. The withdrawal of large amounts, and the heroic resource of aspiration when the flow is not ready, are absolutely contraindicated. OSSIPOw showed by experiments on dogs that serious injury to the nervous parenchyma may result from the abstraction of too great an amount of fluid, from aspiration, and from too frequently repeated puncture. A persistent congestion of the vessels follows the operation, which results, if often repeated, in miliary hæmorrhages in cord and brain.

Finally, there are in the literature several reports of cases in which collapse and sudden death followed the operation within a few hours. These were mostly cases of brain tumor, in which the sudden change of pressure in the cerebro-spinal cavity, due to the removal of fluid, and the compensatory vascular congestion, favored hæmorrhage. The operation is therefore, as a rule, contraindicated in cases of tumor, particularly of the cerebellum, and in all cases of high-grade arterio-sclerosis.

EXTENSION OF TENT TREATMENT TO ADDITIONAL

CLASSES OF THE INSANE.1

By C. FLOYD HAVILAND, M. D.,

AND

CHESTER LEE CARLISLE, M. D.,

Manhattan State Hospital, East, Ward's Island, New York City.

That tent life for the care and treatment of the tuberculous insane, as inaugurated by Dr. A. E. Macdonald, Superintendent of Manhattan State Hospital East, Ward's Island, New York City, has proven eminently beneficial, as shown in the very successful results of "Camp A," there can now be no longer any room for doubt.

That the outdoor tent life has too, a remarkable effect on the demented and uncleanly class is shown also in the awakened mental processes of these unfortunate patients as observed for the last three years in "Camps B and C."

The cases so far mentioned are usually of the most dependent and helpless class. Physically, they are weak, many bedriddenand all require constant nursing and attention. Mentally, their faculties are so enfeebled that they lack all initiative and spontaneity. Their power of attention is limited, their mental content that of the immediate present, their power of association faulty, their retention defective. What concepts they may have are defective, their perceptions obtuse, their ideation a tissue of vague delusions, long of the past, now fading as dementia advances. Their conversation is rambling and incoherent, their deductions fatuous and illogical, their demeanor sullen, apathetic or childishly elated, as the case may be. Many live lives of simple moria.

But another class of patients needs to be accounted for, when considering the effects of outdoor life on the insane. These are the convalescents, those who are on the threshold of the outside world about ready to step back into their accustomed avocations,

'Read at the Sixtieth Annual Meeting of the American Medico-Psychological Association, St. Louis, Mo., June, 1904.