The following is a short abstract of this series of papers, and consists mainly of quotations from the original text on the points of greater interest, omitting, for the sake of space, the various references to the literature of the subject. The large number of insane soldiers under his care has afforded Dr. Mickle a rich field for the study of syphilitic affections of the nervous system, and of the question of the causation of insanity by syphilis:—