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.

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    fying influence upon the specific gravity of the gray matter of the cerebrum. Neither is there any evidence to be gathered from my list of cases tending to show that age has any influence whatever in modifying the specific gravity of other parts of the encephalon. The only fact which it seems desirable to call attention to^ is^ that in both of these children, only two years of age, the white matter of the cerebrum had a very low specific gravity, as well as the deep portions of the corpora striata, and, in one case also, the specific gravity of the medulla oblongata was below the average, whilst in both, the specific gravity of the gray matter and the pons was fully up to the average. Although the specific gravities of the optic thalami and cerebellum were below the average, still the same numbers that were found in these children have been met with in many adults. Influence of Post-mortem Changes.—Dr. Sankey thinks it appears, from a table which he gives, that the mean density of the gray matter is less the longer the post-mortem examination was deferred, while, with the white matter, no such effect is apparent; and also that there is a pretty regular decrease of density equal to about '001 for every twenty-four hours that intervenes between the death and the autopsy. We must say, after due consideration, that Dr. Sankey's facts scarcely seem to warrant his conclusions. He seems to have been influenced a good deal in drawing these conclusions from the fact that in six cases, in which the post-mortem examination was made in less than twelve hours after death, he found average specific gravity greater by 'OOSB than that obtained from twenty-six cases which were examined at periods a little less than twenty-four hours after death. But then he states that of the six ])atients, the post-mortem examination of whom was made thus early, two had severe cerebral symptoms, two slight delirium, and two died sensible. Surely, at the very least, these first two cases should have been omitted from such a calculation; and, if this were done, the discrepancy would be much diminished, so that the fact of the average of four cases, made at a certain period after death, being slightly less than the average of twenty-six made at a certain other period, could have no real weight in determining the influence which the duration of time between the death and the autopsy exercises upon the specific gravity of the gray matter. A.nd more especially is this so when out of these four cases the specific gravity in one was only 1'036, and in another 1033 (actually a low specific gravity rather than a high one). Neither is there a regular decrease in the remaining three series, since whilst the average specific gravity of nine cases, examined at a mean period of twenty-nine hours after death, was 10340, that of nineteen cases, examined at a mean period of forty-four hours after death, instead of being less, as it should have been according to this view, was 1'0347. The direct experiment,