To the Editor: —In his recent communication the director of the Hygienic Laboratory, after detailing what he considers the most important points—adequate dilution and slowness of administration—concludes: "Any physician who fails to observe these precautions should be considered as directly responsible for serious results that follow the improper use of this drug." This statement, if unchallenged, may prove embarrassing to those physicians whose method of administration differs from that advocated. For the past eighteen months, both in private practice and in the out-clinic work at Touro Infirmary, I have abandoned the large dilutions and the gravity method of giving arsphenamin for the syringe and concentrated solutions. During this period, I have given, or supervised the giving of, approximately 2,000 injections of arsphenamin by the latter method. Our routine practice is to dissolve 0.6 gm. of the drug in 20 c.c. of freshly distilled water. The average dose given to an