330 ODOEOGRAPHIA. 



investigation of the constituents of the leaves of GauUheria 

 jyrocumbens, Lin., was made in 1888 by Professor Dr. Frederick B. 

 Power jointly with Xorbert C. Werbke,* which is of such interest 

 and high authority that extracts from their Eeport read before the 

 chemical section of the American Association for the Advance- 

 ment of Science, 16th August, 1888, may here be given : — 

 "... Some difference of opinion prevails regarding the exact 

 relation of this oil to the oil of the Sweet or Black Birch (Betula 

 lenta, Lin.), and but comparatively little is known of the properties 

 of one of the constituents of the former, viz., the terpene. As is 

 well known, the first extended investigation of Wintergree'n oil 

 was made by Proctor, f but its more exact composition was first 

 determined by Cahours,:): who not only ascertained the presence of 

 methyl salicylate, but was likewise the first to observe and 

 mention the presence of an accompanying terpene . . . According 

 to Cahours,§ Wintergreen oil contains 90 per cent, of methyl 

 salicylate, 



/O H 



C O C H3 



(not the isomeric methyl-salicylic acid 



'OCH3 



COOH 



as is frequently and erroneously stated), and 10 percent, of a hydro- 

 carbon or terpene, to which the name gaultherilen has been applied. 

 In his investigations the oil was distilled with concentrated 

 aqueous potash, and the distillate, consisting of wood-spirit (methyl 

 alcohol), water and gaultherilen, w^ashed first with water contain- 

 ing potash, then with pure water, and the undissolved oil 

 dehydrated with calcium chloride and rectified over potassium. 



This terpene, or gaultherilen, is stated to be colourless, mobile, 

 ligliter than water, and to possess a rather agreeable peppery 

 odour. Its composition is given as C^qB.^^, with which the 



* Pharmaceutische Kundschau, Sept., 1888. 



t Amer. Journ. Pharm., xiv., p. 211, and xv., p. 241. 



::: Ann. Cliim. Phys. [.3], x., p. 858. 



§ Ibid., and Gmelin's Handbook of Chem., Cavendish Edit., xiv., p. 290. 



