288 Human Physiology. 



expects that two common hacks will produce a racehorse ; 01 

 that two mongrels will produce a pure hound ; nor can it be 

 more reasonably expected that two scrofulous parents can have 

 a strong healthy child ; two irascible, excitable parents, a gentle, 

 placid child ; or two parents of small intellect and little culture 

 can have a child of genius. When children are "born thieves, 1 ' 

 or " born liars," we expect to find the cause in one or both of 

 their parents or their progenitors. 



For the correction of many physical, mental, and moral 

 peculiarities, we have the law of the attraction of opposites ; 

 but this law does not apply to vices and diseases. In this case 

 " birds of a feather flock together." The ignorant and the 

 vicious, people of low organisations and habits, herd together, 

 intermarry with each other, and beget their kind. Drunkards 

 beget drunkards; dishonesty and lust are hereditary vices. 

 Sensual parents beget sensual children. Diseased parents 

 transmit weakened constitutions and diseased tendencies to 

 their offspring. But nature has provided a terrible remedy. 

 " The wages of sin is death. " Hereditary vices cause disease 

 and hereditary diseases shorten life. The process cannot go 

 onward, because those who violate the laws of health soon 

 lose the power of transmitting their evils to their posterity. 

 Their children die too young to continue the evil stock. Every 

 community living in bad sanitary conditions and habits tends 

 to its own extermination. All large towns are peopled by a 

 constant immigration from the country districts. 



The part which each parent has in giving physical and moral 

 qualities to its offspring is a question of curious, if not impor- 

 tant interest. Abd el-Kadir said the essential forms of the 

 horse were derived from the stallion. The mule of the mare 

 resembles its donkey father, while the mule of the stallion is 

 much more like the horse. Hybrid plants resemble the male 

 parent in foliage and the female in flower. Breeders are very 

 careful in regard to both males and females ; but greater pains 



