STUDY OF BRAINS OF SIX EMINENT SCIENTISTS AND SCHOLARS. 233 



language-arrangement center. As a rule, in the brains of intellectual persons, not only 

 is the left insula the larger and more diiferentiated, but more than this, the preinsula, 

 which is in close juxtaposition with the cerebral centers for articulate speech, is most 

 redundant. The significance of this redundancy of the pre- or postinsula, as the case 

 may be, in its relation to the greater or lesser development of neighboring somesthetic 

 and sense-areas, seems strongly emphasized in the form of the insulse of the cetacea 

 and proboscidea. In these animals the postinsular region is broader, more massive 

 and more convoluted, a feature which, in the cetacea at least, is concomitant with the 

 amplitude of the cortical field of the eighth pair of cranial nerves, the functions trans- 

 mitted by which — both equilibrium and audition — are highly developed in the 

 cetacea. Here we again see how the insula, in its several parts, shares in its develop- 

 ment that of the adjacent sense-center, as in the cetacean brain just alluded toi; and 

 in man, with that of the center for articulate speech. Thus it is that the development 

 of the preinsular region is actually an intense expression of that feature by which the 

 human brain excels that of any other animal. And the more a man be a gifted dia- 

 lectician, the more demonstrable does this redundancy seem to be. Heredity is a 

 potent factor in this connection. As defects in speech are so likely to be repeated in a 

 family line, it seem that its skilled employment by the ancestor is similarly reflected 

 in the way of facile acquirability on the part of the descendant. The speech-faculty 

 in its intimate relations to thought expression, to memory, in its reading-form to sight, 

 in writing to manual muscular innervation, exquisitely hereditary as it is in life, and 

 accurately localizable in the ravages of disease, as shown after death, makes the study 

 of the insula and adjacent regions highly interesting. 



We have seen that men are as variously endowed with intellectual powers as 

 they are with any other traits. It is our business to endeavor to ascertain why and 

 how some are more, some less gifted than others. It is not enough merely to admire 

 the genius of an Archimedes, a Newton, a Michel Angelo or a Bacon ; we wish to 

 know how such men of "brains" were capable of their' great efforts of the intellect 

 and what gave them the capacity for doing great things, as it were, " without taking 

 pains." When we remember that in the human species the brain has attained the 

 highest degree of perfection, and experience teaches that the manifestations of brain- 

 action differ considerably in the races and social classes ; when we remember that all 

 that has ever been said or written, carved or painted, discovered or invented, has been 

 the aggregate product of multifarious brain activity, it seems but reasonable to seek 

 for the somatic bases for these powers and their differences in different individuals. 

 That the brains of men intellectually eminent should come to the hands of anatomists 

 for the jDurposes of correlating, if possible, the encephalic weight, form and fissural 



