Thus, theoretically, at least, it would appear that, if the conjunctiva could be subjected to a temperature as near as possible to this without injury to the tissues, a marked effect should be observed in the course of the disease, particularly if the heat can be applied in such a way as to penetrate as deeply into the tissues as does the gonococcus. This theoretical requirement has, in my opinion, been perfectly met practically by the local use of steam as practiced in the Dimmer Clinic since February, 1913, with the apparatus devised by Lauber and modified by the writer. Goldzieher of Vienna was probably the first to employ steam in the treatment of the purulent ophthalmias; and in his first series of cases reported fifteen patients treated with the application of steam passing through a nozzle held at a distance of about four centimeters from the eye, the temperature of the steam striking the tissues being about 45° C. (113° F.). Although the results indicated that the method was a distinct step in advance there were still a number of important details to be worked out, in order to get the best possible results. First of all, experiment showed that the temperature of the steam at a given distance from the nozzle was not constant, so that an arbitrary distance could not be set. This suggested the advisability of providing the apparatus with a sliding-guard, which could be set at the exact distance from the nozzle where the steam was shown by the thermometer to be at the desired temperature. Secondly, it was determined that the tissues would sustain without injury a considerably higher temperature than that set by Goldzieher, and that the effect upon the diseased process was markedly better when the temperature was raised. Steam at from 50° C. to 53° C. gave the best results; and in one case in which a temperature of 55° C. was inadvertently reached no injury was done the tissues. Further experience naturally suggested other changes in the original technic. In the first place, the lids were held apart by an assistant in the usual manner; but, even with gloves on, the exposure of the fingers to the steam was more or less painful, and gauze wound on little sticks was substituted. The time of exposure was finally set at six minutes; and since the application of the steam could not be borne for longer than from forty-five to sixty seconds without severe pain it usually took twenty minutes or so to complete the six-minute exposure. This was done once every twenty-four hours, and was combined with half-hourly irrigations with potassium-permanganate solution. No other treatment was used. The results attained with this method in 34 cases (7 adults, 2 children and 25 infants) has left nothing to be desired. In no case has there been any corneal complication; swelling and pain subsided with unusual promptness; and the course of the disease was notably shortened, whereas, after the first application of silver nitrate a