Chloride of lime is one of the most useful as well as one of the cheapest disinfectants available. It costs about $25 a ton, although by the pound this wholesale price would not be obtained. It is effective in a 1 per cent solution, that is, 1 pound of chloride of lime to 100 pounds or 12 gallons of water. To be effective, the solution must be well stirred into the organic matter to be disinfected, since it is the chloride rather than the lime which is the disinfecting agent. Saucers or soup plates of chloride of lime standing around the room have no effect upon the germs in the air and on the floor and are of no more value than sulfur, or roses for that matter. Chloride of lime is commonly known as bleaching powder, and its effects on clothes or on any substance which can be eroded is well known. It is, therefore, not a suitable material for disinfecting towels, because the action is on the towel as well as on the bacteria, differing in this respect from mercury, which does not hurt the fiber of clothes. Milk of lime is produced by slaking ordinary building lime until a fine white powder is obtained, about an equal quantity of water to the amount of lime to be slaked being necessary. When the powder has formed and steam has ceased to be given off, then about four gallons of water should be added to each gallon of the powder and the mixture well stirred. This will probably always leave some lime in the bottom of the vessel, since limewater is a saturated solution, and these proportions furnish more lime than is necessary. If not too thin, it is a good whitewash and is a most important agent when used as a whitewash in disinfecting walls and ceilings of such rooms as hospitals and cellars and other places where have been contagious diseases. Milk of lime is an admirable disinfectant in the sick room and generally in houses where infectious diseases have been. It may be poured down drains, into water-closets and privies, and used liberally in all places where bacteria may be supposed to thrive. It must come into intimate contact, however, with the bacteria, and merely sprinkling a little lime dry around the borders of a gutter or drain is of no value. The writer saw, not long ago, a chicken yard where the inspector of a health department had undertaken to secure disinfection by a generous sprinkling of white lime powder around the yard. Such a procedure, however, is not effective, but in a drain the dry powder might be of value because it would later become effective when washed in solution into the drain. Ordinarily, the dry powder is to be avoided. _Soap as an antiseptic._