14 TEE POPULAR SCIENCE MONTHLY. 



In somnambulism the brain is asleep, and this quiescent state of 

 the organ is often accompanied, in nervous and excitable persons, by 

 an exalted condition of the spinal cord, and then we have the highest 

 order of somnambulic manifestations, such as walking and the per- 

 formance of complex and apparently systematic movements. If the 

 sleep of the brain be somewhat less profound, and the spinal cord less 

 excitable, the somnambulic manifestations do not extend beyond sleep- 

 talking ; a still less degree of cerebral inaction and of spinal irritability 

 produces simply a restless sleep and a little muttering ; and when the 

 sleep is perfectly natural, and the nervous system of the individual 

 well balanced, the movements do not extend beyond changing the 

 position of the head and limbs and turning over in bed. 



The phenomena of catalepsy, trance, and ecstasy are also indicative 

 of an independent action of the spinal cord, inasmuch as the power of 

 the brain is not exercised over the body, but is either quiescent or en- 

 grossed with subjects which have made a strong impression upon it. 

 Some of the manifestations of mind shown under such conditions are 

 exceedingly interesting, and are altogether outside of the domain of 

 cerebral consciousness. 



But notwithstanding the fact that the sympathetic system and the 

 spinal cord share with the brain the office of producing mind, there is 

 no question that this last-named organ, immeasurably in man at least, 

 transcends them in power. 



The brain is by far the largest mass of nerve-substance contained 

 in the body of any animal possessing a brain ; indeed, it far exceeds 

 in bulk and weight all the rest of the nervous system together. The 

 researches of European observers give 49|- ounces as the weight of the 

 average brain of the white inhabitants of Europe — the maximum, that 

 of Cuvier, being 64^ ounces, and the minimum, consistent with a fair 

 degree of intelligence, 34 ounces. Webster's brain (allowance being 

 made for disease which existed) weighed 63f ounces. Dr. Abercrom- 

 bie's 63 ounces, and Spurzheim's 55Jg- ounces. The average of twenty- 

 four American brains, accurately weighed by Dr. Ira Russell, was 

 52-06 ounces — the maximum 64 and the minimum 44*25 ounces. The 

 same observer found the average full negro brain, as determined from 

 147 specimens, to be but 46*96 ounces. 



The capacity of Daniel Webster's cranium was the largest on rec- 

 ord, being 122 cubic inches. That of the Teutonic family, including 

 English, Germans, and Americans, is 92 cubic inches. In the native 

 African negro it is 83 cubic inches, and in the Australian and Hotten- 

 tot but 75. The brain of the idiot seldom Aveighs over 23 ounces, and 

 it is often much less than this. In one instance coming under my own 

 observation, the weight of the entire brain was but 14| ounces. Mr. 

 Gore has related in the " Anthropological Review " the particulars of 

 a case of microcephaly in which the brain weighed but 10 ounces and 

 5 grains. The subject, a female, though forty-two years of age, had 



