76 Detection of Adulterations. 



by which the former alkali is usually prepared, and capable of inter- 

 fering with the simplicity of its action on the human system. The same 

 process serves both to detect the impurity and to remove it. It con- 

 sists in treating the morphine with repeated portions of rectified sul- 

 phuric ether ; by which the whole of the narcotine will be dissolv- 

 ed, while the morphine is very slightly acted upon. By evaporating 

 the ether, the narcotine will be obtained separately. Morphine should 

 be entirely soluble in alcohol. 



Oil of Stveet Almonds. — When this oil is obtained from almonds 

 which have been placed in boiling water, it is less mild, and is more 

 disposed to become rancid than when the almonds have not been ex- 

 posed to heat. A very sweet oil is also obtained by pressure, from 

 bitter almonds ; but if these be previously exposed to hot water, the 

 oil will have the odor of hydrocyanic acid, and will not supply the 

 place of good oil. It is sometimes adulterated with oil of poppy seeds, 

 and the impurity may be ascertained by agitating the oil in a vial ; 

 when, if it be so adulterated, bubbles of air will attach themselves to 

 the sides of the vial ; a circumstance which does not occur when the 

 oil is pure. The latter oil gives also to that of almonds, a particu- 

 lar taste, which may be recognised as different from that of the pure 

 oil. 



Oil of Olives. — Tliis oil is sometimes mixed with the oil of poppy 

 seeds; which addition renders it less fit to combine with alkalis, or 

 to form plasters ; and the soaps and plasters made with it, have the 

 inconvenience of adhering to the fingers, on account of their softness. 

 The taste and odor of the oil of poppy seeds are different from those 

 of olives, and the consistence of the former is greatest ; so that when 

 a specimen of sophisticated olive oil is shaken, the bubbles disappear 

 much less rapidly than when the liquid is pure. The pure olive oil, 

 when put into a glass tube, and exposed to melting ice, congeals 

 promptly; while, if sophisticated, the effect is produced less speedi- 

 ly, in proportion to the degree of impurity. M. Poultet employs the 

 nitric solution of mercury for the purpose in question. This solution 

 consists of six parts of mercury, and seven and a half parts of nitric 

 acid sp. gr. 1.373. Mix in a tube, one part of the mercurial solution, 

 and twelve parts of the oil, and shake the mixture at intervals. The 

 mixture will become thick ; and if the oil be pure, will, by the next 

 day, be solid. If the oil of poppy seeds be present, the consistence 

 will be less, in proportion to the quantity of that substance. This 

 test, though not indicating the degree of adulteration with very great 



