TABLE OF THE WEIGHT OF THE BRAIN. 



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ranges between 46 oz. and 53 oz., and that of the female brain between 41 oz. and 

 47 oz. The prevailing weights of the adult male and female brain may therefore be 

 said to range between those terms ; and, by taking the mean, an average weight is 

 deduced of 49| oz. for the male, and of 44 oz. for the female brain, results which 

 correspond closely with the statements generally received. 



Although many female brains exceed in weight particular male brains, the general 

 fact is sufficiently shown, that the adult male encephalon is heavier than that of the 

 female, the average difference being from 5 to 6 oz. This general superiority in 

 absolute weight of the male over the female brain has been ascertained to exist at 

 every period of life. In new-born infants the brain was found by Tiedemann to weigh 

 on an average from 14| oz. to 15| oz. in the male, and from 10 oz. to 131 oz. in the 

 female : a fact of considerable interest in practical midwifery, for it has been shown 

 that difficult labours occur in by far the largest number in the birth of male children . 

 (Simpson, London and Edinburgh Monthly Journal of Medical Science, 1845.) 



With the above results the observations of Peacock, published in the " Monthly 

 Journ. of Med. Science " for 1847, and further observations by the same author in the 

 " Journ. of the Pathol. Soc." in 1860, in the main agree. 



The elaborate table compiled by Rudolph Wagner, and published in his " Yorstudien 

 zu einer Wissensch. Morphol. und Physiol. des Menschl. Gehirns," 1860, containing 

 964 recorded cases in which the weight of the brain had been ascertained, may also be 

 referred to as another recent useful contribution to the knowledge of this subject. 



In illustration of the variation in the average weight of the brain at different ages 

 the following table is given, deduced from the elaborate researches of Dr. Robert 

 Boyd, in the examination of the brains of 2,086 sane persons of both sexes dying in the 

 St. Marylebone Infirmary, and published in the Philos. Trans, for 1860. The weights 

 are stated in oz. avoird. and decimal fractions of them. 



Table of the Weight of the Brain of Males and Females at different Ages. 



Anatomists have differed considerably in their statements as to the period at which 

 the brain attains its full size, and also as to the effect of old age in diminishing the 

 weight of this organ. Soemmerring held that the brain reached its full size as early 



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