Diagram showing one method of locating the Fissure of Rolando (Nancrede). (For location of particular motor and other centres see Fig. 104; also Figs. 105 and 106). Give a method for determining on the skull the position of the fissure of Rolando. The upper end of the fissure is between 6 and 7 inches from the root of the nose, measured on a line taken straight back to the external occipital protuberance. The lower end.-Pass a tape circumferentially about the head on a level with the root of the nose, and bisect this, at right angles, with another tape passing transversely across the head. Then from the point at which this last tape intersects the antero-posterior median line of the head measure down on this tape between 4 and 4 inches. Just a little anterior to this point is the lower end of the fissure of Rolando (Fraser). What are the symptoms of general cerebral compression? Coming on, as a rule, within forty-eight hours after receipt of the injury and following cerebral concussion, they are complete unconsciousness, from which the patient cannot be aroused; pupils unequally contracted or dilated; skin warm; face flushed; temperature 990-100°; heart-action slow and strong; respiration slow, full, and stertorous; at times general convulsions. A milder form some times occurs, in which the unconsciousness is not complete and irritability is marked. What is the course of general cerebral compression? The mild cases commonly end in recovery at the end of a week or so. The severer cases may last for weeks and then recover, but the prognosis is unfavorable. The symptoms as given above are those most commonly seen, and the cause is either hemorrhage or depressed fracture of the skull (traumatic); more rarely cerebral tumor. Should inflammation ensue or occur primarily, then certain other symptoms are superadded or are present from the beginning, as the case may be. What are the causes of cerebral compression? They are hemorrhage, depressed fractures of the skull, the products of inflammation, and cerebral tumors. Discuss the cause of hemorrhage. Hemorrhage which causes cerebral compression is in general known as intracranial, and may be situated (a) between the skull and the dura mater, extradural hemorrhage; (b) between the dura and the brain (including arachnoid and pia or not-no distinction clinically), subdural hemorrhage; (c) within the brain itself, intracerebral hemorrhage. The first is invariably due to traumatism; the second almost always so, but in some cases the vessel-walls may be the seat of pathological changes; while the third variety is caused equally either by traumatism or pathological changes in the walls of the blood-vessels. Intracerebral hemorrhage due to pathological changes in the walls of the blood-vessels is known as apoplexy, of which the symptoms are simply those of general cerebral compression. Of these varieties, furthermore, the first commonly causes general cerebral compression, or at times "local" compression may also be present in the form of either unilateral general convulsions or hemiplegia. (The last two named conditions, by the way, barring out all other causes, represent the extreme degree, as regards the motor apparatus, of local cerebral compression.) The same may be said of subdural hemorrhage, except, in addition, that it has more of a tendency to produce the more limited forms of compression of the motor centres. The third variety induces general or local compression according to its extent and location, or it may cause both. What may be said as to the diagnosis of cerebral compression? The actual condition of cerebral compression, general or local, is, as a rule, sufficiently clear. The question always is as to the causation. And in very many cases this often remains a matter of doubt. This whole question, including treatment, may perhaps be better appreciated by reference to the following table. It is understood, of course, that necessarily only typical cases are therein presented. Complicated cases or those in which more than one cause is operating to produce compression symptoms are not considered. Such cases must be diagnosed by a regard to the combined symptoms of single causes. What are the general principles of the non-operative treatment of general cerebral compression ? Rest. A purge given at once, consisting of extract of jalap and calomel, gr. vj-viij each. In a day or two calomel, gr. 4 t. i. d., may be given right along. Fluid diet. Restraint may be necessary if violence occurs; opium, bromides, and the various hypnotics. Treatment of Cerebral Concussion.-External warmth, elevation of the legs, stimulation by mouth, rectum, or hypodermically. What are shock and collapse ? These are conditions greatly resembling, if not identical clinically with, cerebral concussion. The same treatment applies. Shock may have a mental cause, or result from a blow other than on the head. Collapse is used to describe the condition of a patient resulting from loss of blood, from a long-continued acute illness, from acute intestinal obstruction, or from the ingestion of a gastro-intestinal poison. Saline infusion is indicated through the basilic vein (sodium bicarb. 1 part; sodium chloride 5 parts; water (boiled) 1000 parts) in collapse from hemorrhage. (See also Hemorrhage, under Injuries and Diseases of Circulatory System.) Local suppurative 1. Symptoms of general If local pressure symp- |