420 LATEX 



opium varies from 7 to 35 per cent. Good Turkey opium yields 

 from 4 to 8 per cent, of ash and from 55 to 65 (usually over 60) 

 per cent, of dry aqueous extract (calculated in each case upon the 

 dry opium). 



The quality of opium is, however, determined almost exclusively by 

 the proportion of morphine it contains. Good Turkey opium yields 

 from about 12 to 22 per cent, of anhydrous morphine (calculated upon 

 the dry drug), but is subject, of course, to considerable variation. 

 Persian opium is less rich in morphine, and contains, when of good 

 quality, from 8 to 12 per cent ; in exceptional cases 16 and even more 

 per cent, has been recorded. Indian opium varies from 3 to 15 per 

 cent., the bulk ranging from 7 -5 to 10 per cent. Efforts have been 

 and are being made to raise the morphine content of this variety. 

 Chinese opium has been shown to contain from 4*3 to 11*2 per cent. 

 The alkaloid certainly exists in combination with acids (probably 

 partly with meconic, partly with sulphuric acid), and is easily and 

 completely extracted by water. 



Narcotine varies usually from about 2 to 8 per cent., although the 

 latter figure is occasionally exceeded. It appears to occur in larger 

 proportion in Indian and Persian opium than it does in Turkey, 

 and to exist chiefly in the free state, it being a weak base. Codeine 

 exists in proportions ranging from 0'3 to 4*0 per cent, in combination 

 with acids. Thebaine varies from 0'2 to 0'5 per cent., narceine from 

 O'l to 0'4 per cent. The remaining alkaloids constitute together about 

 1 per cent, of the drug. 



For the preparation of tincture and extract of opium which are 

 standardised to contain 1 percent, and 20 per cent, of morphine respec- 

 tively, any suitable variety of opium may be used provided it contains, 

 when dry, not less than 7 '5 per cent, of anhydrous morphine, but for 

 other official uses opium must contain between 9*5 and 10'5 per cent, 

 of morphine, and opium containing more than 10 per cent, may be 

 diluted with opium containing between 7 '5 and 10 per cent, or with 

 milk sugar. Hence any opium containing over 7 '5 per cent, of 

 morphine may be officially used, the strength being adjusted by 

 suitable blending. This permission was apparently given with the 

 view of favouring the importation of the best varieties of Indian 

 opium. Turkey opium, on the other hand, is occasionally diluted to 

 contain about 10 per cent, of morphine before exportation. 



Adulteration. The necessarily high price of the drug and its nature 

 invite adulteration. Stones, small shot, pieces of lead, and such 

 substances have been found in opium. Gum, grape must, sugary 

 fruits, &c., are said to be added to it. Persian opium frequently 

 contains added gum and sometimes also mineral matter (clay). 

 The percentage of morphine, the ash, moisture, and residue in- 

 soluble in water all give valuable indications, the last-named 



