INTRODUCTION. 23 



torious work on heredity and kindred subjects 

 published in the English language. I have had Authorities 

 the advantage of the libraries of Chicago, Bos- Consulted, 

 ton, New York, and the Medical and Congres- 

 sional libraries of Washington, D. C. The facts 

 and statistics used have been compiled from per- 

 sonal observations and a careful comparison of 

 the most authentic statistics available. The for- 

 mer may be depended upon, the latter are the best 



obtainable. 



i 



Just here, it is proper to say, that we have no 

 absolutely reliable statistics that cover all of the 

 United States. Many states have no enforced 

 registration of births, deaths, pauperism, vice, 

 insanity, or crime. Therefore most so-called au- 

 thentic statistics are but estimations based upon 

 limited observations and are not infrequently 

 highly conflicting. 



The study of heredity, according to the Bible, 

 is as old as civilization. Writers of both the 

 Old and the New Testament scriptures every- _. . 



where recognized the potentiality of heredity. Ages. 

 This is obvious from their frequent references 

 to the inherited superiority of certain families 

 and the necessity of one's being a lineal descend- 

 ant of Abraham, if he was to lay any just claim 

 to greatness. Not only did the ancient Hebrews 

 place special emphasis upon the importance of 

 being born of the seed of Abraham, but they un- 

 questionably understood and practiced the law of 

 selection and prenatal culture. The application 

 of the latter is very plainly set forth in the story an/Heredity? 

 of Jacob dealing with the flocks of Laban, Genesis 

 xxx. In Numbers xiv:i8 we are told that "The 



