390 Intelligence and Miscellaneous Articles. 



ON KREOSOTE. BY M. ItEICHENBACH DE BLANSKO. 



M. Reichenbach of Blansko, to whose labours we owe the disco- 

 very of Paraffine, of Eupione*, and Picamore, has recently found in the 

 products of the destructive distillation of wood a new substance, 

 which he terms Kreosote, from the Greek words xpsxg flesh, genitive 

 by contraction xpew;, and crcog'cy I save. 



This substance is highly interesting, notonlyon account of its che- 

 mical properties, but from its useful application to therapeutics, do- 

 mestic ceconomy, and the preservation of provisions for long voyages. 

 Two processes are given for its preparation. By the one the kreosote 

 is obtained from pyroligneous acid, by the other from the tarry mat- 

 ter which distils over along with that acid. These processes do not 

 differ much ; both are tedious, but the latter method seems to be the 

 easier. The tarry matter yields an oil by distillation, to which, after 

 being rectified and heated, carbonate of potash is added, to neutralize 

 the acetic acid associated with it. The acetate of potash separates, and 

 the oil is again distilled, care being taken to reject the first products, 

 and not to carry the distillation to dryness. The oil that comes over 

 is then treated with a solution of caustic potash ofsp. gr. 1 - 1 2, great 

 heat is produced, and a portion of eupione, &c, formed, which floats 

 on the surface. These are rejected, and the alkaline solution is slowly 

 made to boil in an open vessel. A chemical action takes place, — it 

 absorbs oxygen from the air, and assumes a brown colour. After it 

 is cooled in the open air, diluted sulphuric acid is added until the oil 

 is set free. It is again distilled with water, to which a little caustic 

 potash should be added. The oil is then separated from the water 

 in the receiver, and again treated with a solution of potash sp. gr. 

 1*12, boiled as before — cooled — treated with rather an excess of sul- 

 phuric acid — poured off from the sulphate of potash — well washed 

 with water to carry off the excess of acid — again distilled with water, 

 to which a little phosphoric acid is added, to saturate the ammonia 

 associated with the oil. Lastly, it is dissolved in caustic potash ; and 

 if the preceding operations have been carefully attended to, the kreo- 

 sote and the potash unite, and the mixture, when heated, leaves no 

 residuum of eupione, nor becomes brown by exposure to the air. The 

 kreosote may then be separated from the potash by distillation, and, 

 although not quite pure, is sufficiently so for medical purposes. The 

 foregoing is a very imperfect outline of the process, which will be seen 

 to be sufficiently tedious. The processes will be found minutely de- 

 scribed in the Annals of Schweigger-Seidel, vols. vi. and vii. 



Kreosote is an oily, colourless, transparent liquid, possessing great 

 refrangibility. Its odour is penetrating, disagreeable, and similar to 

 that of smoked beef. It is of the consistence of oil of almonds, and 

 has a sp. gr. of about 1 -037 at 20° Cels. (68° Fahr.) It boils at 203° 

 Cels. (3974° Fahr.) and is not congealed at a temperature of — 27° 

 Cels. ( — 1 6*6° Fahr.) It burns with a smoky flame. It is a non-con- 

 ductor of electricity. At 20° Cels. (68° Fahr.) it forms with water two 

 different combinations, the one containing one fourth part of kreosote 

 in 100 parts of water, the other, ten parts of water in 100 kreosote. 



This substance forms numerous interesting compounds, with acids 

 • See Lond. and Edinb. Phil. Mag. vol. i. p. 402. 



