50 SUBSTANCES SOLUBLE IX ALCOHOL. 



might be made in omitting this treatment, since on rendering- 

 alkaline and shaking with petroleum spirit this solvent wonld 

 take up a little chloroform and would consequently be no longer 

 pure. After, therefore, the remainder of the chloroform has been 

 removed by petroleum spirit, the liquid may be made alkaline 

 ■with ammonia, and the agitation Avith the same solvents repeated 

 in the same oixler. In addition to these three liquids I have, 

 however, after agitation with chloroform, employed amylic alcohol 

 for detecting certain poisons. It removes morphine, solanine, 

 {% 171), saUclne (§ 167), and some other substances from their 

 aqueous solutions with special facility. 



It is princii^ally alkaloids that are removed by petroleum spirit, 

 etc., from ammoniacal solution. Petroleum spirit dissolves, for 

 instance, traces of slnjchnine, hrucine, emetine, cerallne, sahadiUine, 

 and sabatvine. All these substances are, however, more easily and 

 completely taken up by benzene and chloroform. 



But petroleum spirit is specially valuable in the examination 

 for the so-called volatile and, at ordinary temperatures, liquid 

 alkaloids, such as coniine, methylconUne (and conhydrine), nico- 

 tine, lobeliine, sparteine, alkaloids in pimento, capsicum and 

 Sarracenia purpurea. Aniline, trimethylamine, and allied sub- 

 stances are also dissolved by it (§§ 171, 239). In examining for 

 volatile alkaloids I have advised agitation of the aqueous liquid 

 ■with petroleum spirit, and evaporation of the solvent, after sepa- 

 ration, at a temperature of about 20°, on glass dishes previously 

 moistened Avith stiong hydrochloric acid, on which the hydro- 

 chlorides of the alkaloids will partly, at all events, remain 

 behind. A freshly-prepared dilute solution of hydrochloric acid 

 gas in ether may be advantageously substituted for the usual 

 aqueous acid. 



Benzene removes from ammoniacal solution, in addition to the 

 alkaloids already mentioned, atropine, liyoscyamine, jjhysostlgmine, 

 'pilocarpine, gelsemine, taxine, qulnidine, narcotine, codeine, thehaine, 

 delphinine and dclphinoidine, aconitine, aS2)idospermine, pereirine, and 

 a trace of cinchonine. (Cf. § 171.) 



In addition to these, again, chloroform dissolves from ammoniacal 

 solution cinchonine, j^paverine, narce'ine, nvpharine, the alkaloids of 

 celandine, and small quantities of morphine (§ 171). 



J5 57. Direct Tests for (Jlaamdcs, Alkaloids, etc. — The number of 

 acids, glucosidcs and alkaloids (cf. ^21) that may be isolated by 



