In deciding which germicide or antiseptic to use, the dentist should enquire, 1st, which is the most effectual; 2d, which is the safest; 3d, which is the most agreeable to the patient. To answer the first question we must inquire of the experimenter. Dr. Frank L. James, editor of the _St. Louis Medical and Surgical Journal_, a pathologist and microscopist of large experience, has determined, by a series of over eighty cultures carried on during the summer time, covering a period of two months, that campho-phenique, pure, is equal to 1 to 85 of bichloride of mercury, which is six times as strong as it can be used even on the unbroken skin, and about 25 times as strong as is considered safe on cut surfaces. I have purposely omitted comparison with other drugs of this class, as the bichloride was by far the most effectual of any in general use before the introduction of campho-phenique. If these figures are correct, they answer the first question. Certainly, if campho-phenique is from 6 to 25 times as effectual as a safe solution of bichloride of mercury, then it should have the preference in all cases where it is applicable. To the second point, which is the safest germicide, we all should be competent witnesses. The mercuric bichloride is known to be a virulent poison, and therefore ranks lowest in this respect, with carbolic acid closely following it. Campho-phenique is absolutely free from toxic or caustic properties. This I have had frequent opportunity to prove, and no doubt many gentlemen present have had a similar experience. Applied to the unbroken skin it produces no sensation whatever. On cut surfaces there is a slight burning sensation when first applied, followed by anæsthesia. Being non-poisonous, non-irritant, campho-phenique ranks first as a safe germicide. Now to the third point, which is the most agreeable. The brassy metallic taste of the bichloride is intolerable, the taste and smell of carbolic acid and creosote are disagreeable to most people, and the odor and meagre antiseptic properties of iodoform should banish it from the operating room. Campho-phenique has a pleasant odor and agreeable taste, this should establish its claim as the most agreeable germicide. I have yet to hear the first patient complain of its odor or taste. From the foregoing data I am led to conclude— 1st. That when used pure and undiluted, campho-phenique is one of the most efficient and reliable germicides and antiseptics. 2d. Being non-poisonous and non-irritant, it is perfectly safe. 3d. It is the most agreeable to the patient of any drug of its class.