Intelligence and Miscdlaneous Articles. 233 



METHOD OF DETECTING MINUTE QUANTITIES OF OPIUM, IN 

 SOLUTION : BY R. HARE, M.D. 



Through the discoveries of Sertuerner, it is now well known 

 that opium contains an alkaline substance called morphia, to which 

 it owes its efficacy in promoting sleep and relieving pain: also, that 

 this alkali is naturally in union with an acid called meconic, which 

 produces a striking red colour with solutions of red oxide of iron. 

 Nevertheless, this property has not been proposed as a means of 

 detecting opium ; which has probably arisen from the circumstance 

 that the meconate of iron does not precipitate. I have, however, 

 contrived a method by which a quantity of opium not exceeding 

 tiiat contained in ten drops of laudanum may be detected in a half- 

 gallon of water. 



My process is founded on the property which meconic acid has 

 of precipitating with lead. Hence, by adding a few drops of acetate 

 of lead to any infusion, containing any quantity of the drug in ques- 

 tion, not more minute than the proportion above mentioned, an ob- 

 servable quantity of tlie meconate of lead falls down. The precipi- 

 tation, where the quantity is small, may require from six to twelve 

 hours, and may be facilitated by a very gentle stirring with a glass 

 rod to detach the flocks from the sides of the recipient, which 

 should be conical, so as to concentrate them during their descent. 

 The meconate being thus collected at the bottom of the vessel, let 

 about thirty drops of sulphuric acid be poured down on it by means 

 of a glass tube. Let this be followed by as much of the red sul- 

 phate of iron. The sulphuric acid liberates the meconic acid, and 

 thus enables it to produce, with the iron, the appropriate colour 

 which demonstrates the presence of that acid, and consequently of 

 opium. . 



EASY MODE OF OBTAINING MECONIC ACID: BY R. HARE, M.D. 



If to an aqueous infusion of opium we add subacetate of lead, a 

 copious precipitation of meconate of lead ensues. This being col- 

 lected by a filter, and exposed to sulphuretted ))ydroeen, me- 

 conic acid is liberated. The solution is of a reddish amber colour, 

 and furnishes by evaporation crystals of the same hue. A very 

 small quantity produces a very striking effect in reddening solutions 

 of peroxide of iron. 



Instead of sulphuretted hydrogen, sulphuric acid may be used to 

 liberate the meconic acid. The presence of the former, in excess 

 does not seem to interfere with the power of reddening ferruo-inous 

 solutions; but any excess of sulphuric acid may be removed by 

 wliitin;.', which is not acted upon sensibly by the meconic acid. Yet 

 the acid procured in this way did not crystallize so handsomely, or 

 with so much facility, as that obtained by sulphuretted hydrogen. 



METHOD OF PREPARING DENARCOTIZED LAUDANUM: BY 

 R. HARE, M.D. 

 Agreeably to the observations of the French chemists and physi- 

 cians, the un|)leasant effects of opium reside in a principle calle<l 

 New Hcn'oi. Vol '2. No. 9. Sq)f. 1827. 2 II narco- 



