The great majority of the above-described perfumes are made with extracts prepared from pomades; hence their cost of production is considerable and the selling-price high. For the requirements of the middle classes, quite fragrant perfumes are manufactured by dissolving the cheaper essential oils in ordinary alcohol, and various new odors can be obtained by mixing several of them. The extracts made with cheap oils are well suited to this purpose. The oils most frequently used for such articles are those of bergamot, lemon, orange peel, lavender flowers (French), lemon grass, nutmeg, clove, and santal. The alcohol must be free from fusel oil and have a strength of at least 70% Tralles. Oils with not very intense odor are generally used in the proportion of about 2 to 2½ ounces to the quart of alcohol; half that quantity will suffice for strong-scented oils such as those of lemon-grass, clove, and nutmeg. From these simple solutions an experienced manufacturer can produce very nice perfumes by mixing them in due proportions; they are comparatively cheap, and sometimes they yield relatively more profit than the finest articles, whose contents and containers generally represent a considerable outlay on the part of the manufacturer. CHAPTER XV. AMMONIACAL AND ACID PERFUMES. A. AMMONIACAL PERFUMES. Ammonia (ammonia water) has a disagreeable odor and exerts a very caustic effect on the lachrymal glands. Despite these properties, ammonia, in a highly dilute condition and mixed with other aromatics, finds manifold application in perfumery and serves particularly for the manufacture of the so-called smelling salts, or inexhaustible salts, used for filling smelling bottles. The liquid or caustic ammonia, however, is not so suitable for the purposes of the perfumer as the carbonate of ammonia, which when pure forms colorless crystals usually covered with a white dust (consisting of bicarbonate of ammonia); these, undergoing gradual decomposition, give off the odor of ammonia and hence are more lasting in smelling bottles than the pure liquid ammonia. The main essential for both of these substances is purity. Caustic ammonia as well as carbonate of ammonia are now obtained on a large scale from “gas liquor,” but the crude products always retain some of the penetrating odor of coal tar which renders them valueless for the purposes of the perfumer. We must, therefore, make it a rule to use nothing but perfectly pure materials which, moreover, are easily to be had in the market. INEXHAUSTIBLE SALT (SEL INÉPUISABLE). Oil of bergamot 24 grains. Oil of lavender 45 grains. Oil of mace 24 grains. Oil of clove 24 grains. Oil of rosemary 45 grains. Water of ammonia 1 qt. The aromatics are placed in a bottle, the ammonia is added, and the bottle vigorously shaken; the solution is soon effected, and the turbid liquid can be at once filled into bottles.