_Oil stoves_ as first invented consisted of almost the ordinary lamp, without the glass shade set in the stove and were similar to gas stoves. But these were objectionable on account of the fumes emitted. By later inventions the lamp has been greatly improved. The wick is arranged within tubular sliding cylinders so as to be separated from the other parts of the stove when it is not lit, and better regulating devices adopted, whereby the oil is prevented from spreading from the wick on to the other parts of the stove, which give rise to obnoxious fumes by evaporation and heating. Some recent inventors have dispensed with the wick altogether and the oil is burned practically like vapour. _Gasoline_, and other heavy oily vapours are in many stoves first vapourised by a preliminary heating in a chamber before the gas is ignited for use. These vapours are then conducted by separate jets to different points in the stove where the heat is to be applied. The danger and unpleasant flame and smoke arising from this vapourising in the stove have been obviated by inventions which vapourise the fuel by other means, as by carbonating, or loading the air with the vapour in an elevated chamber and conducting the saturated air to the burners; or by agitation, by means of a quick-acting, small, but powerful fan. _Sterilising._--The recent scientific discoveries and investigations of injurious bacteria rendered it desirable to purify water by other means than filtering, especially for the treatment of disease-infected localities; and this gave rise to the invention of a system of heat sterilising and filtering the water, in one process, and out of contact with the germ-laden air, thus destroying the bacteria and delivering the water in as pure and wholesome condition as possible. West in 1892 patented such a system. _Electric Heating and Cooking._--Reference has already been made in the Chapter on Electricity to the use of that agent in heating and cooking. The use of the electric current for these purposes has been found to be perfectly practical, and for heating cars especially, where electricity is the motive power, a portion of the current is economically employed. The art of heating and cooking naturally suggests the other end of the line of temperature--_Refrigeration_.