CREASOTE.
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it is described as an oxiyhydrocarburet {oxy - hydro-car bur e turn) preparedfrom pyroxilic oil.
Natural History. —It is an artificial product; and is obtained by thedestructive distillation of organic substances. It is found in pyroligneousacid, in tar, in Dippel’s oil, in wood smoke, and empyreumatic waters.
Preparation. —The preparation of creasote is a very troublesome andtedious process. The following concise abstract of it is taken from Tur-ner’s Chemistry (5th ed. p. 872). Those portions of the oil (called inthe Pharmacopoeia pyroxilic oil) distilled from wood-tar, which areheavier than water, are first freed from adhering acetic acid by carbonateof potash, and, after separation from the acetate, are distilled. A littlephosphoric acid is mixed with the product to neutralize ammonia, andanother distillation resorted to. It is next mixed with a strong solutionof potash, which combines with creasote, allows any eupion which maybe present to collect on its surface, and by digestion decomposes otherorganic matter: the alkaline solution is then neutralized by sulphuricacid, and the oil which separates is collected and distilled. For thecomplete purification of the creasote, this treatment with potash, followedby neutralization and distillation, requires to be frequently repeated.(For further details I must refer to Dumas’ Traite de Chimie, and to theAnn. de Chim. et Physiq. t. 57, 1834).
Properties. —Pure creasote is colourless and transparent: it has a highrefractive power, and an oleaginous consistence. Its odour is that ofsmoked meat, its taste burning and caustic, its sp. gr. 1.037 at 08° F.It boils at 397° F.; and is fluid at —10'(>° F. It is combustible, burningwith a sooty flame. It absorbs chlorine, and is resinified by it. Nitricacid is decomposed by it, with the evolution of nitrous fumes. Sulphuricacid in small quantity reddens, and in large quantity blackens it. Potas-sium decomposes it, with the evolution of gas (hydrogen ?) and the formationof potash, which combines with some inspissated creasote. It is solublein alcohol, ether, sulphuret of carbon, eupion, naphtha, acetic acid, andacetic ether. It dissolves resins, various colouring matters (as of cochi-neal, saffron, and madder), and some salts (as the acetate of potash). Ithas very little action on caoutchouc; and does not possess any acid oralkaline re-action on test paper. Mixed with water, it forms two combi-nations : one is a solution of 1‘25 parts of creasote in 100 of water; theother, on the contrary, is a solution of 10 parts of water in 100 ofcreasote.
It coagulates the albumen of eggs and of the blood. Concentratedalbuminous liquids are immediately coagulated by it; dilute ones,gradually. Fibrin is not altered by it. It is powerfully antiseptic withrespect to meat and fish. Tar, smoke, and crude pyroligneous acid, owepart, if not the whole, of their antiseptic properties to it. According toMr. J. R. Cormack ( Treatise on Creosote, 1836), the only essential partof the mummifying process practised by the ancient Egyptians was theapplication of such a heat as would first dry up the body, and then de-compose the tarry matters which had been previously introduced, andthus generate creasote.
Characteristics. —The odour of creasote is its most characteristicproperty. To this must be added its combustibility, its oleaginousappearance, its complete solubility in acetic acid and caustic potash, andits action on albumen before mentioned.