Note 100 — Chapter II

The brain of Sónya Kovalévsky was not weighed until it had been four years in alcohol. Prof. Gustaf Retzius then wrote an elaborate account of it and estimated that its weight, at the time of Sónya's death, was 1385 grams. The brain-weight of her illustrious contemporary, Hermann von Helmholtz, was 1440 grams. But when the body-weights of these two eminent mathematicians are borne in mind—Sónya was short and slender—it will be seen that the relative amount of brain tissue was greater in the woman than in the man. Cf. Das Gehirn des Mathematikers Sónja Kovaléwski in Biologische Untersuchungen, von Prof. Dr. Gustaf Retzius, pp. 1-17, Stockholm, 1900.