the descent of inflammatory products. But in the violent purulent cerebro-spinal meningitis, which is occasionally produced by a septic influence, pus around the cord is often continuous with that which bathes the base of the brain. In a case of this kind, in which the meningitis was secondary to acute double purulent otitis, Leyden found abundant active micrococci, very similar to those associated with erysipelas. In other acute cases, organisms have been found similar to those of pneumonia, and met with also in the epidemic cerebro-spinal form.

SYMPTOMS. Slight pain in the back, and malaise, may precede the acute onset of the symptoms. This is usually marked by a rigor, by pyrexia, and by severe pain in the back. The latter varies in posi tion, according to the locality of the inflammation, but is often felt along the whole extent of the spine. Pain also radiates along the distribution of the nerves, round the trunk or to the extremities. This excentric pain is paroxysmal and intense; sharp, darting, burning, or constricting. The pain in the back is usually constant, with exacerbations. It is often increased by movement, usually also by pressure, and by the application of a hot sponge to the skin. It is no doubt due to the irritation of the inflamed meninges, while the radi. ating pain is produced by the irritation of the sensory nerve-roots.

Muscular spasm usually comes on at the same time as the pain. It shows itself first in rigidity of the muscles of the back, most marked, if the inflammation is local, in the neighbourhood of the inflamed part. This rigidity is an important and characteristic symptom. It is often first observed in the neck, probably on account of the mobility of the part. When slight it may merely cause retraction of the head, or stiffness of the back, or may be so general and so severe as to cause opisthotonos, resembling that of tetanus. The spasm usually involves also other trunk-muscles, especially those of the abdomen, which become hard and cramped. The limbs also become rigid, and painful cramp-like spasms occur in them, especially on attempts to move. The spasm is probably partly due to the irritation of the motor nerve-roots, and is partly reflex, from the irritation of the sensory roots and the nerves of the pia mater. There is usually great hyperesthesia of the skin to all forms of stimulation, and also increased sensitiveness of the muscles, especially in the lower limbs. Pressure on the arms may cause no uneasiness, while a similar pressure on the legs occasions great pain. Reflex action is usually increased at the beginning. Constipation is common, and so is retention of urine, in spite of irritable attempts to empty the bladder-the result, apparently, of spasm of its muscles, including the sphincter, which resists the action of the detrusor. Dyspnoea may result from the spasm of the thoracic muscles, and may be almost suffocating in its severity. The pulse may be frequent or retarded. The temperature is raised, sometimes, however, to only a slight degree. Cerebral symptoms, headache, delirium, coma, occur

when inflammation has extended within the skull. The Cheyne. Stokes breathing" may be present, from implication of the medulla. The function of the vaso-motor nerves (which leave the cord by many of the anterior roots) is also deranged; the dilatation of the vessels, that follows a stroke on the skin of the trunk, is excessive and prolonged (meningeal streak, tache spinale).

As the disease progresses, the symptoms of irritation give place to those of paralysis, which may be most marked where the rigidity was greatest. The limbs become relaxed, and feeble or powerless. Sensibility becomes lessened or lost. Reflex action disappears, the muscular power in the limbs becomes so reduced that the patient is scarcely able to move; the heart shares the universal prostration, and death may occur from asthenia, or from paralysis of the respiratory muscles. Towards the end there is sometimes considerable rise of temperature. In some cases the symptoms become less progressive and the disease passes into a less acute stage; the pains persist, the loss of power continues and may even slowly increase. Death may occur, after weeks of suffering, from the effects of bedsores or from secondary kidney disease, due to the retention of urine, and facilitated by trophic derangement. On the other hand, in slight cases, the signs of irritation may lessen and pass away, while those of structural damage, paralysis and anesthesia, may remain, and to these may be added muscular atrophy and contractures, from the secondary consequences of the lesions of the nerve-roots. Such persistent symptoms vary much in extent and degree, according to the position and intensity of the morbid process. Ultimately the symptoms of damage to the cord may either slowly increase, in consequence of the spread of chronic myelitis set up by the acute mischief, or, on the other hand, the symptoms of the meningitis may pass entirely away.

The symptoms above described vary in their distribution, according to the position of the disease. When the membranes over the lumbar enlargement are chiefly affected, the pains, hyperesthesia, and cramps are confined to the legs and loins. When the disease is in the dorsal region there may be similar hyperesthesia and spasm in the legs, but the pain and cramp extend higher, and involve the trunk. If the cervical region is affected, the symptoms extend to the upper extremities, the dyspnoea may be great, and there is often difficulty in swallowing. The action of the heart is sometimes deranged, and contraction or dilatation of one or both pupils may occur. Extension to the brain is marked by vomiting, general headache, delirium, and paralysis of cranial nerves, of which the first to suffer are the spinal accessory and hypoglossal. If such symptoms preceded those of spinal meningitis, we may conclude that the inflammation commenced within the skull.

The symptoms vary somewhat according to the nature of the inflammation. In purulent meningitis, as already pointed out, the symptoms of irritation are sometimes very slight, apparently because

there is little tendency to invade the nerve-roots. In the case from which Figs. 90 and 91 were taken, there were hardly any symptoms to suggest meningitis, and, although there was paraplegia, it was probably produced by the mere pressure of a large collection of pus on the spinal cord; there were no pains or spasm. The case was one of septic origin. It was apparently a pure arachnitis, and the tissue of the pia mater was able to resist invasion so completely as to protect the structures beneath it even from disturbance of function.

The duration of the acute symptoms varies from a day or two, in severe cases, which end in death, to two or three weeks, in cases of less severity, which may end in either death or recovery. The duration of the subacute and chronic symptoms that supervene is to be measured by months, and sometimes by years.

The symptoms of tubercular spinal meningitis resemble those which have been described, but are usually less intense. There is pain in the back and loins, with stiffness of the spine and retraction of the neck, so that it may be difficult to bend the head forwards. There are also variable rigidity, hyperesthesia, and tingling in the limbs, followed by lessened sensibility and paraplegic weakness. These symptoms occasionally come on in the later stage of cerebral tubercular meningitis. DIAGNOSIS.-The diagnosis of the disease rests on the pain in the back, the retraction and rigidity of the neck and spine, the hyperæsthesia and spasm in the limbs, excited especially by attempts to move them, on the acute onset of the symptoms and on their association with pyrexia. This grouping of the symptoms is sufficiently characteristic, as is shown by the fact that it is extremely rare for them to be simulated, even remotely. The chief difficulty in actually acute cases is presented by the forms that run an almost latent course, especially by the secondary purulent form, which has so little tendency to invade the nerve structures, and a correspondingly slight tendency to derange their functions, and even to irritate them. In pure myelitis, on the other hand, pain in the back is absent or trifling; paralysis occurs early and is the leading symptom, and there is little or no spasm in the limbs in the early stage of the affection. Often, however, some meningitis occurs at the onset of acute myelitis, and then some pain in the back and slight rigidity in the limbs may precede or accompany the onset of the paralysis. In such cases the predominance of the meningeal or cord symptoms must determine the category in which the case is to be placed. Meningeal hæmorrhage most nearly resembles meningitis in its manifestations, and does so necessarily, because it produces inflammation; the distinction chiefly depends on the onset, and will be considered in the next section. Hæmorrhage into the spinal cord can scarcely be confused with inflammation of the membranes, because the only common symptom, pain in the back, is confined to a definite spot.

Tetanus is attended by rigidity of the back, and by spasm, and presents a closer initial resemblance to meningitis than most other

affections with which it may be confounded; but there is no fever at the onset, trismus is an early and obtrusive symptom, and the paroxysms of muscular spasm are excited by peripheral impressions much more readily than in meningitis, in which they occur chiefly on attempts to move. Only the " rheumatic" form of tetanus would give rise to difficulty; the onset of the traumatic form after an injury should prevent any doubt. Rheumatism of the muscles may cause pain in the back on movement, and the resulting rigidity may prevent movement; but there is not the spontaneous pain which attends meningitis, nor is there distant spasm. Some difficulty may be caused by rheumatism of the cervical muscles in young children; this may lead to retraction of the head, and if it comes on acutely, after exposure to cold, considerable doubt as to its nature may at first be felt. But it remains stationary, and the freedom of the patient from spontaneous or radiating pains, and from any affection of the nerves, soon enables a reassuring opinion to be formed.

The diagnosis of the form of meningitis depends on the recognition of the cause of the inflammation. When spontaneous and acute the case is probably of the "primary" form, which depends on some toxic agency, probably often an organised virus, and is really a partial "epidemic" form. If it occurs under the conditions that give rise to surgical septicemia, or after childbirth, purulent meningitis is almost certain, and the inflammation may be far more intense than the severity of the symptoms suggest. The diagnosis of tubercular spinal meningitis depends on the combination with cerebral meningitis, which usually precedes the spinal symptoms, and on the gradual and insidious onset. Indications of the tubercular or scrofulous diathesis are commonly present in the state of other organs, or to be ascertained from the family history of the patient.

PROGNOSIS.-The prognosis is grave in all cases. It is worse the more severe and acute the symptoms, the higher the temperature, and the sooner the symptoms of irritation give place to those of paralysis. It is worse also when the disease is due to serious lesions of the spine or to tuberculosis, than when due to cold, and worse in the so-called "spontaneous" cases than in those which result from traumatic causes. Recovery is more probable in middle life than in early or advanced age. The previous health of the patient also influences the prognosis. It must always be remembered that even if the patient survives the period of acute inflammation, serious permanent damage may remain. TREATMENT.-Perfect rest and quiet are of the greatest importance throughout the course of the disease. All sounds should be, as far as possible, excluded; the light should be subdued, and all bodily movement and mental exertion as far as possible avoided. The vascular disturbance of inflammation is intensified by all functional excitement of the too irritable structures, and continuous freedom from such excitement, as far as it is possible to obtain the freedom, is of paramount importance. Every attack of spasm means greater vascular

disturbance, and the circulatory derangement entails leucocytal infil. tration and other structural consequences.

Although it is undesirable that the spine should be the lowest part of the body, yet, in acute meningitis, it is scarcely possible for the patient to lie in any other posture. The prone position interferes with respiration, and both it and a lateral posture entail, directly or indirectly, greater muscular exertion, and hence more frequent and more severe attacks of spasm, with secondary harm out of proportion to that which the posture could prevent. Here, as so often in therapeutics, skill is shown and success secured, if it is within reach, by knowing when to permit no compromise, and when to adopt one. The dorsal position must be permitted if in it the spasm is much less than in others. Dry, or, in robust patients, wet cupping, or leeching, along the spine may be employed at the onset, and be followed by the local application of cold in traumatic or hæmorrhagic cases, and of heat in others—the principles being the same as in myelitis. Counter-irritation, by blisters or repeated sinapisms, is more useful when the disease is subsiding than at the onset. In cases that are due to cold, free diaphoresis often does good; a hot air or vapour bath should be employed at the onset of the treatment. A warm bath may be followed by moist packing for several hours. The relief thus given is sometimes very great. The bowels should also be freely opened.

The only internal remedy which has been held, for long, in general repute, as capable of influencing the inflammatory process, is mercury. The confidence placed in it of old is not altogether unwarranted. It should be given until there is a slight affection of the gums (the only evidence that enough is in the system to act on the tissues), and inunction is unquestionably the best way of adminis tration. We know that it must then enter the blood before it can escape by the bowel; we can regulate its dose as we need, for we estimate it by the influence on the gums; and by rubbing it in over the part affected we can combine some counter-irritant influence (as by an irritating agent added to the ointment used), and we necessarily secure the simultaneous action of the two agents, for the largest quantity of mercury in the blood will coincide with the most considerable reflex action on the vessels. Lastly, the disturbance of the stomach and bowels is certainly less than when their mucous membrane is chosen as the path into the body. The oleate of mercury may be rubbed in along the spine. Iodide of potassium seems to have little influence over acute inflammation.

It is necessary to give sedatives for the relief of the pain and spasm, if the application of cold does not suffice. Of these, morphia, given by the skin or the mouth, is the most effective, but vomiting from its use is a grave drawback; fortunately it does not readily occur under the circumstances. Sometimes inhalations of chloroform are necessary to relieve the suffering, and may be even more effective