With a proper distribution of the heated water through pipes, and radiators of sufficient heating surface, all rooms can be warmed to an equal temperature. Another consideration is the economy in fuel when properly constructed heaters are used, for the water readily absorbs the heat and retains it for hours after the fire has ceased to burn. Unlike steam heating, a moderate fire will warm the house in moderate weather. Hot water heating does not exclude a practical scientific system of ventilation. There is no danger from explosion, nor from fire, the plant is absolutely odorless and noiseless, and requires neither mechanical skill nor close attention to run it. There is no doubt of the durability of a hot water system, for if properly constructed it should last as long as the building, and the cost is less than a number of mantels with the necessary flues. The most comfortable average temperature for living rooms is from 65 to 70 degrees Fahr., for hospitals and sick rooms a higher temperature is generally required, say from 75 to 80 degrees Fahr. Dr. Horace Dobell, of London, in his work entitled “Winter Cough,” makes some very practical and useful remarks, when he says: “But before leaving the subject of sudden changes of temperature, I must not forget to speak of sleeping rooms. It is quite astonishing what follies are committed with regard to the temperature of sleeping rooms. On what possible ground people justify the sudden transition from the hot sitting room to a wretched cold bedroom, which may not have had a fire in it for weeks or months, it is impossible to say, but it is quite certain that the absurd neglect of properly warming bedrooms, is a fruitful source of all forms of catarrh. We cannot too much impress this upon our patients.” There is another source of danger in artificial heating, and that is, in having the air of the house always much warmer than the most favored temperature of the open air. This is a great mistake because it is under these circumstances almost impossible to go from an overheated house or apartment into the open fresh air without catching cold, and for this reason the thermometer should be found in every well-regulated household. Women who are under treatment for female disease should never get into a cold bed, even if there has been fire in the sleeping room during the day. In damp and cold weather there should be greater precaution in this respect. The best bed warmer is one or more earthenware jugs, like the German seltzer water jugs, filled with hot water. Earthenware radiates the heat better and retains the warmth longer than glass, while there is no danger of the heat cracking the jug, as it will glass bottles. One or two of these jugs filled with hot water and put into a bed an hour or so before retiring will bring the temperature up to an agreeable warmth.