108 FIXED OIL, ETC. 



an alkaline aqueous solution also gradually assumes a red tinge. 

 It is decomposed by fusion with potash, yielding, amongst other 

 substances, butyric acid (the same is the case with filicin). 



Eaphoihon^ is likewise soluble in petroleum spirit, and freely 

 so in ether, benzene, chloroform, acetone, and glacial acetic acid, 

 but not in aqueous alkalies. It dissolves in concentrated sulphuric 

 acid, with the production of a brownish tinge, which is changed 

 to violet by nitre or nitric acid. It melts at 113° to 114°, and 

 resembles, in many of its properties, lactucon or lactucerin (various 

 species of Lactuca), echicerin (dita bark), and perhaps also cynan- 

 chocerin (Cynanchuni vincetoxicum and acutum). 



Ileleiiin is easily soluble in petroleum spirit, alcohol, and ether, 

 but insoluble in water, even in the presence of a little alkali ; it is 

 dissolved, however, Ijy hot concentrated solution of potash. 

 Helenin melts at 110°, crystallizes in colourless needles, and dis- 

 solves in cone, sulphuric acid, with production of a red colouration. 

 Hydrochloric acid-gas is also said to colour helenin red.^ 



Coumarin may be recognised by its odour and by its colourless 

 rhombic crystals. It is sparingly soluble in cold, more easily in 

 hot water, and is also dissolved by ether and by alcohol. Amongst 

 the substances it yields Avhen fused with potash is salicylic acid 

 (§ 26). For the allied melihitic acid compare Zwenger.^ 



Styrol also is characterized by its aromatic odour. It is a colour- 

 less liquid convertible by long heating in sealed tubes into solid 

 metastyrol. It is almost insoluble in water, but easily soluble in 

 alcohol, ether, and bisul})hide of carliou. Heated with chromic 

 acid it yields benzoic acid and other products of decomposition 

 (§20). 



For myroxocarpin, see Stenhouse and Scharlingj* for dio-iviln, 

 Landerer^ and Fluckiger;*^ iov kämpfe rid, Brandes and Jahns/ 

 for asaron (which is soluble at least in warm petroleum spirit), 



^ Hesse, Annal. d. Chem. und Pharm, clxxx. 352; clxxxii. 1(J3, 1876; 

 cxcii, I'Xi, 1878 (Amor. Journ. Pharm. 1. 552). See also Albert! and Dragen- 

 dorff, Pharm. Zeitschr. f. Pussland, ii. 215, 1863; and Fliickiger, N. Jahrb. 

 f. Pharm, xxix. 135, 1868. 



- See Kallen, Ber. d. d. chcm. Ges. vi. 1506, 1873 (Pharm. Journ. and 

 Trans. [3], vii. 156). 



•* Annal. d. Chem. und Pharm. Suppl. v. 100, 1867. 



* Ibid. Ixxvii. 306, 1851, andxcvii. 69, 1856 (Anier. Journ. Pharm, xxiii. 144). 



^ Repert. f. Pharm. Ixxxiv. 62. 



" Ibid, xxiii. (New Series), 102, 1874 (Amer. Journ. Pharm, xlvi. 235). 



^ Archiv d. Pharm. Iviii. 52 ; Ber. d. d. chem. Ges. xiv, 2385. 



