On the specific gravity of different parts of the human brain / by H. Charlton Bastian.

  • Bastian, H. Charlton.
Date:
1865
Catalogue details

Licence: Public Domain Mark

Credit: On the specific gravity of different parts of the human brain / by H. Charlton Bastian. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

    7/52 (page 5)
    at tlie tables will at once show that the specific gravity in the cases of insanity was almost uniformly higher, and this observation applies to both the gray and the white matter. He gives the mean spe- cific gravity of the gray matter as 1'0391, the lowest density met with being ] 030, and the highest, 1'049 ; and the mean of the white as 1'0424, with extremes varying between 1034 and r053. Dr. Skae also examined the cerebellum of twenty-seven insane patients, as well as in a few sane individuals, and after comparing the results, he says : From these data, although limited, I infer that the specific gravity of the cerebellum is increased in insanity, and attains a greater increase in relation to that of the cerebrum than it does in persons dying sane. In an article on The Pathology of Insanity,* Dr. Bucknill has given a very interesting table compiled from the results of post- mortem examinations in sixty-three cases of insanity, and including more recent observations upon the specific gravity of the brain. These latter results are the more valuable because in the case of the cerebrum, he has now given us the benefit of his observations upon the specific gravity of the gray and white matter taken sepa- rately. He found the specific gravity of the gray matter in the insane to vary between 1'030 and 1'048, and the average to be 1037, wdiilst that of the white substance varied between 1033 and 1-046, and had a mean of 1-039. Dr. Bucknill also gives the average specific gravity of the cerebellum in this series as 1-040, the extremes being 1-030 and 1-049; he does not state, however, whether these results were from the examination of the whole organ, or of parts only, as in his previous experiments. Dr. Peacock has published more recentlyt a limited number of observations upon the specific gravity of the encephalon, cere- brum, and cerebellum, and of the combined pons and medulla. The difference now ascertained to exist between the specific gravities of the pons and of the medulla oblongata when taken separately, render an examination of their combined specific gravity unde- sirable for the future. The method employed by Dr. Peacock was different from that adopted by previous observers; he resorted to the process of weighing in air and then in distilled water, and deducing the specific gravity of the body from its observed loss of weight in water, by a proportional formula. Of course, with a delicate balance and due precautions, this method would be as capable of yielding accurate results as the other, but it must not be forgotten that during the process of weighing in water, there would be the same difiiculties to contend with as Dr. Bucknill speaks of in his attempts to ascertain the specific gravity of the cerebrum as a whole, * .January, 1855, p. 207, ' Brit, and For. Med.-Chir. Review.' t ' Trans, of Patholog. Soc.,' vol. xii (1860-61), p. 27.