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Author : Le Bon Gustave
Title : Experimental Researches on the Variations of the Volume of the Brain and Skull
Year : 1878

Link download : Le_Bon_Gustave_-_Experimental_Researches_on_the_Variations_of_the_Volume_of_the_Brain_and_Skull.zip

Messieurs, I have the honor of delivering to you several conclusions that appear in a work on the variations of the volume of the brain and skull¹ that I shall soon be submitting to the Society. These conclusions are based on a considerable number of measurements that I have executed upon live subjects or upon skulls belonging to the Society’s Museum, and also from unpublished records whose access I owe to the graciousness of Doctor Broca. The data have been expressed in the form of line graphs which, as some of you know, have been displayed in the anthropological sciences section at the Universal Exposition. 1. The variations of the volume of the skull in the human species are greater and much more apparent than those differences that are visible when one restricts himself to a comparison of averages. Within the same race these variations are very considerable. For example, by weighing 100 Parisian skulls belonging to the male sex, it will be seen that their weight will vary between 1,000 and 1,700 grams. The capacity of an equal number of skulls of the same sex will show that the volume of these skulls ranges between 1,300 and 1,900 cubic centimeters. These extreme amounts are linked to each other in a progressive manner. In mixing together all the races and both sexes, one will recognize that the capacity of the human skull may normally vary nearly 100%, that is, from a simple, small size to one almost twice as large. Many factors, of which the principal one is the level of intelligence, determine these variations or their correlates. 2. The average skull capacity of the superior races considerably surpass that of the interior races, but what really constitutes the superiority of one race over another is that the superior race contains many more voluminous skulls than the inferior race. For every 100 modern Parisian skulls examined, there are generally 11 subjects whose skull capacity falls between 1,700 and 1,900 cubic centimeters, whereas in the same number of Negroes one does not find any whose skull possesses the previously-indicated capacities. In the very inferior races, the most voluminous skulls hardly ever exceed 1,500 cubic centimeters. Comparing the largest skulls belonging to the superior races to the largest skulls of the inferior races, the difference amounts to the enormous number of 400 cubic centimeters. By contrast, the difference between the average capacity of skulls belonging to these respective races is only a little over 200 cubic centimeters. ...