1835.] Improvements in Science. 211 



double its volume of water, to which a sufficient quantity of 

 sulphuric acid has been added to enable the fluid containing 

 the creozote to swim on the surface. The liquid is then 

 boiled for some minutes. After cooling, the colourless 

 liquid below is separated, and the brown oil is rectified in 

 a retort. The product may again be subjected to the same 

 treatment with sulphuric acid and water. The colour is 

 still brown, but after being separated from eupion it is 

 pale-yellow. 



In order to separate the eupion, the rectified product 

 should be dissolved in a solution of caustic potash, according 

 to Reichenbach's method. 



The supernatant oil is separated, the ley heated, and 

 after cooling, it is converted by sulphuric acid into a solu- 

 tion of sulphate of potash and creozote, which swims on 

 the surface. The latter may be obtained colourless, by 

 washing it in water mixed with a slight excess of solution 

 of potash, and then distilling it. Hubschmann considers 

 that, as an agent in medicine, its powers have been greatly 

 overrated, and that the only use which ought to be assigned 

 to it is its application for ameliorating the pain of carious 

 teeth. 



Picamare, [pix amara] {Schweigg. Jour, lxvii.) — Reichen- 

 bach gives this name to a substance obtained from tar-oil, 

 which, by repeated distillation, being brought to a sp. gr. 

 of 1*08, is mixed with caustic potash of sp. gr. 1*15, in the 

 proportion of 1 part to 8. In the course of two days a 

 compound of picamare and potash is formed, which may be 

 decomposed, and the picamare obtained by acids. Creosote 

 remains in the mother liquor. Pure picamare is colourless, 

 greasy, with a strong smell, inflammable, and bitter tasted, 

 boiling at 120° C, (248° Fahr.) It is insoluble in 1000 parts 

 of water, to which it imparts a bitter taste. It dissolves in 

 any proportion in ether, sulphuret of carbon, and petro- 

 leum, and does not combine with paraffine and eupion. It 

 unites with chlorine, iodine, bromine, phosphorus, sulphur, 

 and selenium, and dissolves in sulphuric and nitric acids. 

 It . crystallizes immediately with all alkalies, even with 

 ammonia. 



Paraffine (parum affinis.) — When tar from beech wood is 

 distilled to dryness, three liquids pass over into the receiver, 



p2 



