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DR. J. BARNARD DAVIS ON THE WEIGHT OF THE BRAIN 
justified in making the assertion, which he said could not be regarded as a hypothesis, 
that Nature, inasmuch as a certain size and mass of brain is a necessary condition for 
the exercise of the faculties of the mind, hath furnished the people of all human races 
herewith in an equal degree, he was compelled to have recourse to a series of secondary 
influences to account for the diverse intellectual state of mankind. It was the hypo- 
thetical error of his system that led him to insist on the physical unity of man; his 
intellectual inequality could not be denied*. On the other hand, Professor Huschke 
affirmed that a difference in the weight of the brain in different races cannot be mis- 
taken, with which the stature may correspond. He adds, thus the German brain 
exceeds in the mean 1400 grammes, the French has been by many observers specified 
to be only 1300 grammes, and that of the small Hindoos and indigenes of Bombay 
amounts to only 1000 to 1100 grammesf. It will be easier to test the correctness of 
these and various other statements, after our Tables have been examined. 
The importance of the average stature and weight of the body, so variable in different 
races, in their relations to the size and weight of the brain, although these relations 
have not yet been properly investigated, has not been overlooked. The large Germans 
and the small Hindoos are obvious instances. Up to the present time, exact observa- 
tions upon the stature and weight of the races of man are almost wholly wanting. The 
notes to the Tables will include some information upon these points, in the cases in 
Avhich it can be obtained. 
The weight of the brain is much influenced by sex and by age. In the following 
Tables the sexes of the crania have been determined, as accurately as may be from their 
examination, where they have not been otherwise known. They are always distinguished 
in their relative numbers. This was omitted in Morton’s Table, as may be mentioned 
with regret. The observations have been confined to the skulls of adults. Any more 
definite rule respecting age it was not easy to lay down. The brain-weights have been 
arranged in six Tables, corresponding very much with the races of the six great divisions 
of the globe. In all cases, the estimated weight of the heaviest brain of the series is 
given first, then that of the lightest, and last the average weight of the whole. By the 
insertion of the averages of each sex and of the whole series, as much is done as may be 
to correct the preponderance of those individual exceptional cases of large brains, mega- 
locephali, and small brains, microcephalia which occur in probably all races of man. 
In general it has not been thought necessary to exclude from our estimates either 
synostotic or artificially distorted skulls. The effects of synostosis are almost always 
much confined to limiting the development of the cranial cavity in one direction, whilst 
it has received a corresponding expansion in another compensatory direction ; so that 
there is no material diminution in the mass of the cerebral matter contained in the 
skull. In the cranium of the Stettin Weaver, the most remarkable example of syno- 
* Professor Tiedemann’s Memoir was read before the Royal Society in 1835, and appears in the Philosophical 
Transactions, vol. cxxvii. The reference is here made to the German edition, Das Hirn des Negers mit dem 
des Europaers und Orang-Outangs verglichen, 1837, S. 47. 
t Schsedel, Him und Seele des Menschen und der Thiere, 1854, S. 60. 
