131 



with a purified cotton plug in the neck, and loosely stoppering the same while the 

 filtrate rolleeted in a 100 cc flask. Excessive evaporation was thus avoided. With 

 samples of a suitable degree of fineness 100 cc could be decanted without difficulty. 



One worker filters the final solution of alkaloid in volatile solvent before evaporat- 

 ing <>n the latter. If the funnel be kept covered during filtration, and if the filter be 

 properly washed, losses may be avoided and the alkaloid obtained in a cleaner con- 

 dition than without filtration. 



DISCUSSION OF RESULTS. 

 ACONITE ROOT. 



This sample was delivered as No. 40 powder. The following proportions passed 

 through the respective sieves: 



Grams. 

 \". HO 



.0 7 



10 n 



No. 20 82 



Total /....loo 



M'.-t ,,f the powder was therefore coarser than the Pharmacopoeia directs for assay 

 samples. 



The throe gra\ imetrie results by Method I are too few in number to base upon them 

 any conclusion Only :',_' p-r eent of the volumetric results by Method I (U. S. P.) 

 come within 1<> \ -r rent of the average and only 59 per cent come within 15 per cent, 

 and tin- results, both 'jravi metric and volumetric, by (II) are, on the whole, as bad 

 or worse. Tin- a\ rau r <- n-snlts by the two methods are in very good agreement, but 

 considerably under the I'nited States Pharmacopoeia standard of .0.50 per cent. It is 

 quite possible that higher and more uniform results might have been obtained with 

 a finely pou.l. ',-d sample. 



On comparison of the corresponding gravimetric and volumetric results by (II) 

 whirh we may assume were obtained by weighing and then titrating the same alka- 

 loidal rv-iilin-. it will be observed that in about one-half the instances the volumetric 

 result i- hi-ln-r than th. irnivinn'tric, though it can not be assumed that these residues 

 absolutely pun- alkaloid. The factor for aconitine (0.064) employed in 

 computing tin- \olumetri< result is too high, and the residue contains alkaloidal mat- 

 ter of lower molecular w.-i-ht than 640, resulting from the decomposition of aconitin. 

 It i- probubli- that the volumetric results by (I) are affected by a similar error. These 

 << moderations tend to support the contention of Doctor Lyons and others that chem- 

 ical assay's of aconite should be confirmed by the so-called "physiological test." 



In Method, I Mr. Fuller considers the evaporation of the alcoholic percolate to dry- 

 ness at a temperature not exceeding 60 as too tedious, and carried evaporation only to 

 the point where alcohol was all expelled, acidifying the aqueous residue with normal 

 acid and filtering as usual. lie also washed the acid solution with ether before mak- 

 ing alkaline and shaking out. A number of workers note the usual difficulty in fil- 

 tering the acidified residue from evaporation. Mr. Hankey added powdered pumice 

 to the residue to aid filtration and titrated finally with half-strength lime water. He 

 found the marc on repeating the extraction yielded no more alkaloid. Mr. La Wall 

 in a parallel experiment shook out finally with chloroform-ether mixture instead of 

 ether and obtained lower results, viz, gravimetric 0.35 per cent and volumetric 0.416 

 per cent. Doctor Lyons used paper pulp to aid filtration, and after the final shaking 

 out with ether further shaking out with chloroform yielded about 0.1 per cent alka- 

 loid, titrating 0.07.~> per cent as aconitin and producing its characteristic effect on the 

 tongue. He believes that aconite assays should be confirmed by the Squibb physi- 

 ological test. He also suggests a direct titration method for aconite, similar to the 



