On the chemical pathology of the brain / by Adam Addison.

  • Addison, Adam.
Date:
[1866]
Catalogue details

Licence: Public Domain Mark

Credit: On the chemical pathology of the brain / by Adam Addison. Source: Wellcome Collection.

    12/24 (page 12)
    Gorap Besanez, in summing up, observes, that the foregoing quantitative analyses present no deductions of definite value bearing upon pathological conditions or mental diseases. Perhaps not, but when we find that Bibra's analyses of insane brains were limited to three or four cases at most, it seems to me inexpedient and baneful to the progress of exact knowledge that the inquiry should be closed. It is by no means impossible that deviations from the normal quan¬ titative composition will be found in diseased conditions and func¬ tions of the brain, and in many cases of paralysis and other diseases limited to definite parts of the cerebrum it will be interesting to ascertain the difference between the healthy and unhealthy parts. It is with this view that I communicate the results of my own work. I shall first state the processes by which my results were obtained. As soon as possible after removal from the calvaria the brain was stripped of its membranes, and portions of the different regions weighed on watch glasses, on a balance turning with 100th of a grain. The anatomical parts analysed are the same as in Bibra's cases; but it appeared to me more correct to examine the gray and wThite sub¬ stance of the hemispheres separately, so that I have one column more than this author has. The gray matter was carefully scraped off the white with a scalpel. The weighed portions were then dried at a temperature of 230° Fahrenheit, until after repeated weighings they ceased to lose weight. The loss was deducted as water. After the calculation of the water the fats were extracted from the dried portions of brain in an apparatus recommended by Bibra. Into a small glass flask of suitable size an air-tight cork is fixed, through which a strong glass tube, about six or seven inches in length and half an inch in diameter, reaches half way down into the flask. This tube, at its lower end, is furnished with a small open¬ ing 3—5 lines in size; into its upper end a perforated cork is fitted, through which another tube, bent twice at a right angle, connects the apparatus with a second flask. The bent tube leads through a perforated cork, not quite air-tight, to the bottom of the second flask, which should be well cooled in water. Into the strong tube, winch reaches half-way dowm into the first flask, the substance to be extracted is placed, and the extracting material (the ether) in the flask belowr. When the ether is warmed and brought to boiling by a lamp, the hot vapours ascend through the small opening in the end of the tube, soften the substance there, dissolve as much as they are able to take up, and remain partly concentrated and fully saturated in the tube, while the superfluous ether is distilled through the bent pipe into the second flask. AY hen a certain quantity has collected into this the lamp is removed, and the natural consequence is that the distilled ether returns with some force into the first flask and carries with it the fat which has been concentrated in the tube. Bibra says that