In addition to its employment in ordinary spirit lamps, where it is burned directly by means of an ignited wick, alcohol is used as a source of heat in various appliances for warming, cooking, and other operations. These appliances include stoves for heating small rooms; ovens, boilers, and hot plates for cooking; blowpipes for soldering and brazing work; burners for laboratory use; and heaters for flat-irons, curling-tongs, and other domestic articles. In general the principle adopted for these forms of heating apparatus is that of the Bunsen burner; the alcohol is vaporised, and the vapour mixed with air is ignited. The blowpipes are fed with alcohol, or with a mixture of alcohol and a hydrocarbon oil ("carburetted ' alcohol) under pressure applied by means of a small hand-pump.. Freedom from smoke, soot, and ash is an advantage of these heating appliances compared with coal fires.

"Solidified" Spirit. - This product, which is used for burning, is a mixture of soap and methylated alcohol, containing usually about 5 to 7 per cent. of soap. The latter is produced within the spirit by saponifying stearin with sodium carbonate or hydroxide, the mixture being heated. On cooling, the soap forms a bulky, soft solid which occludes the spirit.

One variety is made by melting 45 parts of stearin, adding 0'5 part of sodium carbonate and 95 parts of methylated spirit, and heating the mixture for an hour in a closed vessel.

An American recipe is as follows: Alcohol 1,000 c.c, stearic acid 60 grams, sodium hydroxide 13.5 grams. Dissolve the stearic acid in one-half of the alcohol, and the sodium hydroxide in the other half. Warm each solution to 60°. Mix them, and pour into suitable containers which have previously been warmed to 60°, and allow to solidify.

A patented "solidified alcohol burning without soot " is composed of ethyl alcohol 60 parts, methyl alcohol 40 parts, and sodium stearate 2-3 parts.1

Colouring matter such as methyl violet is sometimes added to these preparations.

Instead of soap, collodion may be used; the process is rather more costly, but the product has a better appearance. In general, these spirit-soaps and collodions are used mainly as domestic luxuries such as toilet lamps or travelling spirit-lamps; they are too expensive for employment as industrial combustible substances. The soap preparations, however, put up in small tins, have been found very convenient for use as little ' cookers "by troops on active service.

According to a note in the Chemical News,2 the discovery of "solidified spirit" was due to an attempt to hoodwink the Paris octroi officials. Some years ago an unscrupulous individual, in order to deceive the officers, conceived the idea of pounding up white grated soap in a mortar and mixing it with an equal weight of alcohol. He thus obtained a sort of homogeneous paste, which he moulded into cakes, and passed through the octroi without difficulty. The alcohol was then recovered by simple distillation on arriving at its destination. This device presently brought its author into the police court, but the process was taken up again in. an honest manner, and was the origin of the present methods of preparing " solid" alcohol. It is one of the rare services which fraud has rendered to trade.