_Methods of Administering Mercury._--(1) _By the Mouth._--This was for long the most popular method in this country, the preparation usually employed being grey powder, in pills or tablets, each of which contains one grain of the powder. Three of these are given daily in the first instance, and the daily dose is increased to five or even seven grains till the standard for the individual patient is arrived at. As the grey powder alone sometimes causes irritation of the bowels, it should be combined with iron, as in the following formula: Hydrarg. c. cret. gr. 1; ferri sulph. exsiccat. gr. 1 or 2. (2) _By Inunction._--Inunction consists in rubbing into the pores of the skin an ointment composed of equal parts of 20 per cent. oleate of mercury and lanolin. Every night after a hot bath, a dram of the ointment (made up by the chemist in paper packets) is rubbed for fifteen minutes into the skin where it is soft and comparatively free from hairs. When the patient has been brought under the influence of the mercury, inunction may be replaced by one of the other methods, of administering the drug. (3) _By Intra-muscular Injection._--This consists in introducing the drug by means of a hypodermic syringe into the substance of the gluteal muscles. The syringe is made of glass, and has a solid glass piston; the needle of platino-iridium should be 5 cm. long and of a larger calibre than the ordinary hypodermic needle. The preparation usually employed consists of: metallic mercury or calomel 1 dram, lanolin and olive oil each 2 drams; it must be warmed to allow of its passage through the needle. Five minims--containing one grain of metallic mercury--represent a dose, and this is injected into the muscles above and behind the great trochanter once a week. The contents of the syringe are slowly expressed, and, after withdrawing the needle, gentle massage of the buttock should be employed. Four courses each of ten injections are given the first year, three courses of the same number during the second and third years, and two courses during the fourth year (Lambkin).