The chemical composition of B. matter averages in 100 parts— Water 751 parts.
Albuminous matter 7 " • Fat 111 " Salts (containing 11 of phosphoric acid) 6 " The proportion of these constituents varies not only in different species of animals, but also in different members of the same auhnal group, and appears to be much influenced by the age, temper, and intellectual capabilities of each individual. Thus, the normal quantity of salts in the B. of a healthy man is 6 per cent, and in the 13. of an insane patient, only 2+ per cent were found.
S(ftening of the brain (rawollissement) is a frequent result of chronic inflammation of the brain. The patient has been for some time in low health, troubled with headaches, loss of appetite, depression of spirits, and a gradual loss of memory, and acute percep tion of things in general. Then a spasm may occur, followed by paralysis, or the legs and arms may be bent up, and remain in that position. This condition of 13. may be caused by of proper nourishment to the cerebral substance, owing to plugging up, or from disease of its arteries. When the softening is caused by inflammation, we frequently find pus forming an abscess of the brain. Induration may also occur as the result of inflammation.—The other diseases, as hydrocephalus, will be treated under their own names.
_Diseases of the brain.—lnflammation (acute) of the B. (phrenitis, or popularly, brain fever) rarely occurs separately, and can scarcely be distinguished from inflammation of its membranes (meningitis). According to Dr. Watsmi of London, when the disease begins in the latter, the first remarkable symptom is a convulsion fit; when in the 13. substance itself, nausea and vomiting generally usher in the attack.
In the first stage, there is rapid pulse, severe headache, the eyes suffused, and their pupils contracted to a small point, very intolerant of light. The patient is constantly watchful, and much annoyed by even ordinary sounds. Then furious delirium sets in, And lasts for n period, varying with the case, generally from twelve to forty-eight hours; when it is succeeded by collapse, in which the patient lies—his face devoid of color, and covered with cold sweat—in a state of stupor. If roused, he now speaks }with slow, indistinct utterance; his pupils are now dilated. and indifferent to the brightest light: and the loudest speaking ceases to annoy him. The stupor increases with the general prostration. and continues till death. After death, we find serous fluid upon the B., deposits of lymph, thickening of the membranes, and softening of the 11. substance itself.
General and local bleeding, with antimony and digitalis. to subdue the, pulse; mer cury, to prevent the deposit of lymph; blisters, as counter-irritants. to the back of the head and neck, are the usual remedies for this tare, but terrible disease. The younger school of practitioners, however, as Dr. Tanner expresses it. prefer waiting to see if nature unaided, or only gently guided, will not carry the patient through a disease where the efforts of art are notoriously futile, and are rather content to watch the symptono. to calm excitement by sedatives, to lessen increased heat of body by diluents and tepid sponging, to prevent accumulations in the intestines by purgatives, and to diminish -maniacal delirium by the application of cold to the head.