WIXTEKGREEX. 339 



the methyl ether of this compound, by the action of methyl iodide 

 and caustic potash on wintergreen oil ; it is a liquid boilinc^ at 

 244°-246^ C. ' 



Salicylic acid, C- Hg O3, can be obtained in purity from natural 

 oil of wintergreen by the follo\Ying process : — Dissolve three parts 

 of pure caustic potash in 2 parts of water in a glass or porcelain 

 vessel, and raise the temperature to 180^ Fahr. Stir into this 

 gradually 3 parts of wintergreen oil, using a glass or porcelain 

 spatula. Into another vessel place 64 parts of cold distilled 

 water and add 8 parts of hydrochloric acid, then, with constant 

 stirring, add the salicylate of potassium. The magma of minute 

 crystals of salicylic acid which forms must be separated 

 with a thin muslin strainer (previously moistened) and 

 pressed, then dried by exposure to a temperature of 150"^ 

 Fahr. The yield of this crude acid will be slightly over 2 

 ports. Dissolve this in 6 parts of cold alcohol and filter through 

 a funnel stopped with cotton. Then, with constant stirring, pour 

 the filtrate into 32 parts of cold water. The magma of minute 

 crystals must be separated with a thin muslin strainer and dried 

 by exposure to a heat of 150^^ Fahr. 



It was long ago observed by Gerhardt that salicylic acid 

 decomposes on heating into phenol and carbon dioxide. Salicylic 

 acid is now manufactured in a wholesale way synthetically bv 

 Kolbe and Lautemann's patented process, i.e., by the action of 

 carbon dioxide on a mixture of phenol and sodium* : English 

 Patent Xo. 595, 1874. The former chemist found that it was also 

 formed when carbon dioxide is passed over heated sodium phenate, 

 half the phenol being set free.f There are also other ways of 

 preparing it synthetically. 



Other Ericaceous plants are known to yield oils analogous to that 

 of G. Procumhens] such as, Gaultheria leucocarpa,^a native of 

 Java and very common in woods on the sunnnit of Mount Gede, 

 Mount Patoea and other extinct volcanoes. It is known by the 

 natives under the name of Zantigi hadas. This plant was found by 

 De Vrij§ to yield from the fresh leaves 0-012 per cent, of essential 



* Ann. Cheni. Pharm., cxv., p. 201. 



+ Journ. Prakt. Chem. [2], x., p. 89 ; described in 1st series, p. 166. 

 X Blunie, Bijdragen tot de Flora van Nelerlanclie Indie, p. 856. 

 § Pharm. Journ. [3], ii., p. 503. 



