302 
Original Communications. 
be boiled in four ounces of pure or rain water, if this also forms 
a clear solution in its boiling state, add 5 or 6 drops sulphuric 
acid to convert it into a super-sulphate, which is much more 
soluble; let it stand in the flask till nearly cold, then add caus- 
tic water of ammonia gradually, until it ceases to give a pre- 
cipitate. Collect the precipitate on a filter, and wash it with 
a small portion of water, and carefully dry it at a low tempera- 
ture, not exceeding 100,° lest it run into a mass. Weigh the 
precipitate, which is pure quinine, and if the sulphate was pure 
should amount to 39^ grains, any deficiency, if the experi- 
ment has been carefully conducted indicates the amount of 
impurities. Neither of these experiments are sufficient alone 
to establish the purity of the article, yet the successful result 
of the two will be sufficient to establish it; and one or both, 
will detect any article (so far as my knowledge extends) that 
would be likely to be found mixed with it. In all these ex- 
periments, the sulphate of quinine is spoken of in its dry crys- 
talline state ; if the article has become effloresced by exposure 
to the air or heat, 10 per cent, must be deducted for the wa- 
ter which it has lost. 
It is better to dry and balance the paper before it is used to 
filter with, and then should the quinine become fused by heat, 
the result can be equally attained, deducting for the weight 
of the paper. 
To the Board of Trustees of the Philadelphia College of Phar- 
macy. 
Since our recent appointment by the Board, there has been 
submitted to us for examination, a sample of sulphate of qui- 
nine, containing a considerable quantity of impurity. This 
article was put up in one ounce vials, and bore the label and 
seal of Delondre, Nogent, near Paris. A large quantity of it in 
broken vials was sent to Farr & Kunzi, operative chemists of 
this city, for the purpose of having it recrystallized — and the 
impurity was thus discovered by them. 
