SULPHATE OP QUININE. 
189 
tallizations, there is much animal black and residues from ni- 
trations which retain much quinine. For a long time I sub- 
jected these residues, &c. to a treatment with hot acidulated 
water, after a sufficient quantity had become accumulated to 
render it worth while; this solution was precipitated and crys- 
tallized in the usual manner. 
"When I received the account of your experiments, I 
carefully examined every step of my process, and paid espe- 
cial attention to the treatment of the animal black and niters, 
and discovered that the action of the sulphuric acid was suffi- 
ciently powerful to act on the animal charcoal, in the different 
washings, and thus to carry off a portion of the phosphate of 
lime and magnesia contained in it. 
" To remedy this I now drain the precipitate perfectly and 
treat the washings with alcohol, and it is remarkable that I 
thus obtain a larger and whiter product than heretofore, not- 
withstanding the bulk of the first was increased by the foreign 
admixtures. 
" Hence according to the quantity of these residues operated 
upon, might be the proportion of foreign substances, though 
wholly unknown to me, and even to my loss. I have care- 
fully analyzed several lots of the quinine of commerce, and 
found that much gave T J^- to T | 7 of impurities, and in the 
impure residue after calcination also found in commerce, I 
have found T J F , and in one instance, T £_. 
" Since the adoption of my new method, I test the product 
of each operation, and have not found more than T | ^ in the 
residue by incineration, and no appreciable portion in that 
by alcohol." 
Mr. Delondre concludes by stating that he has requested 
his agent in London to transmit 25 oz. of his Sulphate of Qui- 
nine to the Philadelphia-College of Pharmacy, to experiment 
upon and otherwise dispose of, as may be deemed most expe- 
dient. He also adds that any additional details will be fur- 
nished that the College may desire. 
Mr. Delondre also transmitted a certificate from Mr. 
Bussy, Professor of Chemistry in the School of Pharmacy at 
