122 Heredity. 



There are others of a more obscure nature, which give us a 

 glimpse of the curious relations between talent and insanity. 

 Long before Moreau of Tours' celebrated thesis in regard to 

 genius, Gintrac had noticed the following fact : a father touched 

 with insanity had able sons, who filled public situations with dis- 

 tinction. Their children appeared at first sensible, but at the age 

 of twenty became insane. In twenty-two cases of hereditary in- 

 sanity, Aubanel and Thore have noticed two facts of this kind. 



Deferring, for a while, the difficult question of the metamorphoses 

 of heredity, we here give only similar, and, consequently, the most 

 indisputable, cases, and they also are the most frequent. There 

 are families the members of which, with few exceptions, are all 

 subject to the same kind of insanity. Three relations were placed 

 at the same time in a lunatic asylum at Philadelphia. In a Con- 

 necticut asylum there was once a lunatic the eleventh in his 

 family. Lucas mentions a lady who was the eighth. More curious 

 still, this infirmity often appears at the same period of life in suc- 

 cessive generations. All the scions of a noble family at Hamburg, 

 distinguished through four generations for great military talents, 

 went mad at the age of forty : there remained but one member, a 

 soldier like his father, and he was, by decree of the senate, forbidden 

 to marry ; the critical period came, and he also went mad. (Lucas.) 

 A Swiss merchant saw two of his children die insane both at the 

 age of nineteen. A lady went mad at the age of twenty-five after 

 childbirth; her daughter became insane at the same age, also after 

 childbirth. In one family the father, son, and grandson committed 

 suicide at about the age of fifty. (Esquirol.) 



ii. 



We now proceed to show from examples that the chief varieties 

 of mental malady are transmissible. In the absence of any 

 universally accepted classification, we group our facts under the 

 following heads : Hallucination, Monomania, Suicide, Mania, 

 Dementia, Idiocy. 



Hallucination assumes two principal forms. Sometimes it results 

 from the automatic action of the nerve-centres, and is compatible 

 with perfect reason; hallucination in this case does not imply 

 error of judgment: it is recognized as an illusion, nor is the subject 



