The contagious diseases which are propagated by the sexual relations are two in number, and are technically known as gonorrhoea and syphilis. They both commence by some local manifestation, and may not proceed further; but about as often they rapidly extend to the whole system, and produce effects upon it which are as permanent in character as those by vaccination or other specific virus.

By far the most insidious and destructive is syphilis. This is supposed by some writers to have been unknown in Europe until about the period of the discovery of America. And not a few historians maintain that it was conveyed from the natives of the West Indies to the inhabitants of the Old World by the sailors of Columbus. Certainly about that time it broke out with unparalleled virulence in the camps, courts, and brothels of Spain, Italy, France and England. No country was willing to father it, so the English called it the " French disease;" the French, "le mal de Naples;" the Italians, " la mallattia della Spagna."

There is good reason, however, to believe that neither Columbus, the Indians, nor any one of these nations was solely to blame in the matter. Probably it had lurked unrecognized and under comparatively innocent forms through all races and ages. At the epoch referred to, the massing of great armies by Francis I. and Charles V., and the increased commerce, acting together with some change in the human constitution itself, led to a violent outbreak in its most virulent form. Some have imagined that the ancient leprosy, so often referred to in the Old Testament, was one of its forms; and others, that it was derived from the glanders in the horse, transplanted into the human economy. But these theoretical views are of little public interest, and it is enough to remember that, about the year 1500, a very malignant type of the disease arose and spread with fearful rapidity, and that since that time it has been rightly deemed one of the scourges of the human race.

The other form of secret disease, gonorrhoea, was well known to the ancient Romans, and to the lawgivers of the middle ages, and old English statutes of the fourteenth century concerning brothels distinctly refer to it as "the perilous infirmitie of burnynge." It, too, appears to have increased in frequency and severity about the same time as syphilis, and is to-day certainly much more severe than it was even in the dissolute commonwealth of imperial Rome. So far have a riper civilization, a more advanced medical science, and a purer morality failed to curb these insidious complaints, that they are now probably more widely distributed than ever before, and little, if at all, abated in violence. The only point which we have actually gained - and this certainly is much - is to treat them with greater success than hitherto.