Hereditary Disease

The inheritance of disease is one of the most mysterious and deplorable conditions of humanity. Any suggestions that may tend to throw light on the laws which regulate the development of hereditary diseases, with a view to their prevention or alleviation, cannot fail to interest not only the physician or philosopher, but all mankind; for how few of us can boast of an ancestry entirely free from some form of hereditary taint. How often does it become the painful lot of the physician to see some member of a family, who had given every promise of health and a brilliant career, struck down by an attack of insanity, which his friends would fain attribute wholly to some accidental cause, mental or physical, but which the experienced medical man discovers, on close enquiry, to be the development of constitutional disease, transmitted from some member of the family more or less remote. If he does not find evidence of decided insanity (for friends and relations will often take infinite pains to conceal this fact), he will probably discover that some have manifested the existence of hereditary disease in the form of phthisis, scrofula, epilepsy, &c. Having made the connection between these diseases and insanity the object of close observation and study during many years, the conviction of their having a common origin became so strong to my mind that, in 186^, I published a treatise on the subject.* Since that time extended observations have confirmed my belief in the truth of