[2] The three so-called venereal diseases are syphilis, gonorrhea, and chancroid or soft ulcer. Gonorrhea is the commonest of the three, and is an exceedingly prevalent disease. In man its first symptom is a discharge of pus from the canal through which the urine passes. Its later stages may involve the bladder, the testicles, and other important glands. It may also produce crippling forms of rheumatism, and affect the heart. Gonorrhea may recur, become latent, and persist for years, doing slow, insidious damage. It is transmitted largely by sexual intercourse. Gonorrhea in women is frequently a serious and even fatal disease. It usually renders women incapable of having children, and its treatment necessitates often the most serious operations. Gonorrhea of the eyes, affecting especially newborn children, is one of the principal causes of blindness. Gonorrhea may be transmitted to little girls innocently from infected toilet seats, and is all but incurable. Gonorrhea, wherever it occurs, is an obstinate, treacherous, and resistant disease, one of the most serious of modern medical problems, and fully deserves a place as the fourth great plague. Chancroid is an infectious ulcer of the genitals, local in character, not affecting the body as a whole, but sometimes destroying considerable portions of the parts involved. Let us think of syphilis, then, as a serious but by no means hopeless constitutional disease. Dismiss chancroid as a relatively insignificant local affair, seldom a serious problem under a physician's care. Separate syphilis from gonorrhea for the reason that gonorrhea is a problem in itself. Against its train of misfortune to innocence and guilt alike, we are as yet not nearly so well equipped to secure results. Against syphilis, the astonishing progress of our knowledge in the past ten years has armed us for triumph. When the fight against tuberculosis was brought to public attention, we were not half so well equipped to down the disease as we are today to down syphilis. For syphilis we now have reliable and practical methods of prevention, which have already proved their worth. The most powerful and efficient of drugs is available for the cure of the disease in its earlier stages, and early recognition is made possible by methods whose reliability is among the remarkable achievements of medicine. It is the sound opinion of conservative men that if the knowledge now in the hands of the medical profession could be put to wide-spread use, syphilis would dwindle in two generations from the unenviable position of the third great plague to the insignificance of malaria and yellow fever on the Isthmus of Panama. The influences that stand between humanity and this achievement are the lack of general public enlightenment on the disease itself, and public confusion of the problem with other sex issues for