HEREDITY 217 



that constitutes the movement, and which, con- 

 sidered as a series, is the rhythm of this force. 



Those who are born now and become familiar 

 with the daily use to which electricity is applied 

 have a great advantage over those who were born 

 fifty years ago. The man born to-day in a civilised 

 town and in a large capital (I am, of course, speak- 

 ing of a healthy individual) has a very great 

 advantage over one born in an uncivilised country. 

 The brain of him who lives in an atmosphere of 

 high culture acquires a large amount of knowledge, 

 which by its stimulus influences the associations 

 established by the neuronas among themselves, 

 and influences also the increase in the number of 

 the collateral ones, that in their turn extend the 

 degree of association of some ideas with others ; 

 and this constant stimulus will in its turn influence 

 the successive development of humanity, increasing 

 in successive generations the number of the 

 neuronas, which is what happens from the inferior 

 animals to man. The normal difference that must 

 exist between parents and offspring is that variable 

 quantity that supposes the greater adaptation to 

 the external, and which may be acquired from one 

 generation to another. 



Sick parents, or those who have altered the 

 normal state of their formula N, through over- 

 fatigue, alcoholic excess, or any other cause, or 



