384 ODOROGKAPHIA. 



aqueous distillate with ether and afterwards evaporating the ether. 

 It can also be obtained from the crude empyreumatic oil of coffee 

 by distillation with ether, and after separating the oil, agitating 

 the aqueous distillate with water, as above. It is a brownish 

 coloured oil, heavier than water, boiling at 195'^-197^ C, and 

 possessing the fine aroma of coffee in a very powerful degree. It 

 is slightly soluble in boiling water ; an almost imponderable 

 quantity of it is sufficient to aromatise more than a quart of 

 water.* Its alcoholic solution gives with ferric chloride a red 

 coloration which is not destroyed by sodium carbonate. It only 

 dissolves with difficulty in concentrated caustic potash solu- 

 tion, and on fusion with caustic potash yields salicylic acid. It is 

 therefore probably a methyl-ether of saligenin, and has the 

 constitution C^ H^ (0 H) C H. C Hg.f The fact that it gives a 

 red coloration with ferric chloride, which shows it to be a phenol, is 

 in accordance with this supposition. Eotsch has also found that 

 liyclroxybenzyl methyl ether, which is isomeric with caffeone, 

 smells strongly of burnt coffee, but loses the smell completely on 

 purification. This behaviour may be explained by the formation 

 of small quantities of caffeone as a by-product, to which the crude 

 product owes its odour. 



Hydroxybenzyl methyl ether, Cg H^ (0 C H,.) C H. OH, is formed 

 when saligenin, C- Hg 0^, is heated with methyl iodide, caustic 

 potash and wood spirit. It is a liquid which boils at 247^'5 C.,and 

 solidifies in a mixture of ether and solid carbonic acid to a glassy 

 mass. \ 



A method for preparing Saligenin was devised by Piria, as 

 follows : — Fifty parts of salicin are put into 200 parts of water, 

 and 3 parts of emidsin added (this substance being obtained by 

 macerating pressed almonds with 3 parts of water for 24 hours and 

 precipitating the solution with alcohol. See series i., p. 176). 

 After 12 hours, the greater portion of the saligenin has crystallised 

 out, and the remainder is extracted from the solution with ether. 

 The crude product is then re-crystaUised from hot benzene. § 

 Saligenin dissolves in 15 parts of water at 22^ C, and in almost all 

 proportions in boiling water, readily in alcohol and ether. It 



* Pelouse and Fremy, Traite de Chimie, iv., p. 449. 



t Ann. Chim. Phys., xliii., p. 440. 



X Ber. Deutsch. Cliem. Ges., v., p. 436. 



§ Am. Cheni. Joiirn., cxvii., p. 84. 



