QUESTION OF PHYSICAL DEGENERATION 257 



The following table shows at anyrate that 'where the taint cf 

 deafness already exists, consanguineous marriage increases the likeli- 

 hood of transmission. 



We must, therefore, be careful not to attribute the whole of 

 the evil to the fact that the deaf in recent years have been more 

 generally educated, and consequently have more frequently 

 intermarried. 2 



But though the frequency of deafness is, no doubt, in some 

 communities largely due to consanguineous marriages, any in- 

 crease of frequency must be due to some other cause, since there 

 is no reason to believe that marriages between relations have 

 become more common. We must, therefore, conclude that 

 where congenital deafness has recently grown more prevalent, 

 it is traceable to the systematic education of the deaf which has 

 been proved to result in a great increase of the marriage-rate 

 among them. 



There is no doubt that there is a serious increase of the 

 tendency to deafness, but it is quite possible to quote figures 



1 Marriages of the Deaf, p. 108. 



2 Mr Huth in his book, The Marriage of Near Kin, concludes that no bad 

 results follow from such marriages. Rigid Natural Selection among domestic 

 animals, no doubt, makes inbreeding even beneficial. When Natural Selection 

 is less stringent, as among men, serious evil often results. 



