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

  • Henry Charlton Bastian
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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    also, which Dr. Sankey introduces to show that the sujiposed dimi- nution in density is due to changes in the brain after death, appears to us to throw no hght whatever upon the question. For liow is it possible to judge from the change taking place in the gray matter of a portion of brain, which was simply wrapped in paper during the time that elapsed between the first and second exami- nation, and lay uncovered in the dead-house on a plate, between the second and third experiments—the weather being cold and wet, as to what would be the changes taking place in a brain still within the unopened cranium. It appears to me, therefore, that there is no satisfactory evidence to show either what, or whether any, influence is exercised upon the specific gravity of the brain by the length of time intervening between death arid the post-mortem examination. Connection between absolute weight of brain and the specific gravity of its white and gray matter.—There seems to be no corre- spondence whatever between these conditions, and we can quite agree with Dr. Sankey in his conclusion that, the heaviest brain neither has the lightest specific gravity, nor the contrary; nor has the lightest brain the lowest specific gravity of either white or gray matter. Influence of the duration of the last illness on the specific gravity. —From an examination of one of his tables, Dr. Sankey is inclined to beheve that there is a general tendency in the gray matter to decrease in density as the length of the last illness increases, but the decrease proceeds much less rapidly after the seventh day than it appears to do up to that date. A consideration of the nature of the five cases, in which the examination took place before the seventh day, in conjunction with the fact that a regular diminution docs not take place in the average specific gravities, given in Dr. Sankey^s table, of the gray matter in persons dying after successively longer periods of illness, would of itself be sufficient to show the very un- satisfactory nature of the evidence upon which this conclusion is based. Dr. Sankey admits that the evidence is very slight, but still he seems disposed to attach more weight to it than might have been ex- pected. He seems to think that in active health the density of the gray matter is usually high, but this seems to be little else than a mere supposition, since it receives no necessary support what- ever from the fact that, in many cases of acute disease where the individual dies after a short illness, the sjjecific gravity of the gray matter is found to be high. This high specific gravity may simply be a product of the acute disorder itself, so that it is just as likely that the antecedent specific gravity had been increased by the dis- ease, as to suppose that there was no time to lower tlie initial high specific gravity of health owing to rapidity of death. The influence of the nature of last illness, and of symptoms pre-
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