Geography of Man in Relation to Eugenics 293 



with the same defect. Thus with regard to deaf mutes, 

 Bell says: "The practice of the sign language hinders the 

 acquisition of the English language; it makes deaf mutes 

 associate together in adult life, and avoid the society of 

 hearing people; it thus causes the intermarriage of deaf 

 mutes and the propagation of their physical defect." The 

 importance of this barrier is seen among recent immigrants. 

 These tend to herd together, largely because of a desire to be 

 with people who speak the same language. Thus immigration, 

 instead of directly tending to promote matings of dissimilar 

 and unrelated blood, has, at first, an exactly opposite effect. 



The barrier of race is of the very greatest importance in 

 promoting marriages of kin — especially if one race be in a 

 marked minority, as the Negroes are in New Hampshire 

 and the whites are in the Mississippi River bottom, around 

 Vicksburg, or in parts of the West Indies. 



Finally the barrier of religious sect has been erected 

 again and again to insure the intermarriage of the faithful 

 only. This is illustrated by the teachings of the Society 

 of Friends and smaller sects, such as the Dunkers, Shakers, 

 and Amish. Of the Dunkers it is written: "In their early 

 history marriage out of the church was punishable by 

 expulsion.^ It is still frowned upon but the process of 

 liberalization now in progress had modified the attitude of 

 the church. In some congregations families intermarry 

 generation after generation. But the degree of kinship is 

 not so close that any evil results appear in the offspring." 

 Nevertheless one sees the danger that any small sect 

 with such tenets runs. A critical study of the Amish of 

 Pennsylvania with much marriage of kin shows a sufticient 

 progeny of epilepsy and crippled children to ser\'e as a 



^ Chronicon Ephratcnsc, 96, 246. 



