FALSIFICATIONS AND ADULTERATIONS. 
57 
price current, of a large house, and I am happy to add that it 
is not a Philadelphia house, quoting this " Sp. nitri dulc." at 
nine cents per pound! Can any one believe that this is spirit 
of nitrous aether? 
Oxalic Jlcid. — An eminent professor of chemistry in one 
of our universities, writes to us that a quantity of this acid, 
which he recently purchased in another city, and which was 
doubtless imported from abroad, contained about one-third its 
weight of supertartrate of potass. Its purity may readily be 
tested by dissolving it in a sufficient quantity of water, add- 
ing carbonate of lime cautiously, until effervescence ceases, 
filtering, drying the precipitated oxalate of lime, and observ- 
ing that for every hundred grains of oxalic acid, if pure, 
there should be a product of about two hundred and five 
grains of oxalate. As, however, in operating on a small 
quantity, a slight difference of weight, which might be pro- 
duced by the presence of tartrate of lime along with the 
oxalate in the precipitate, might not be observed, the purity 
of the acid may be still more satisfactorily ascertained, by 
digesting this supposed oxalate of lime in a solution of tar- 
taric acid, and again drying it. Should any tartrate have been 
present, it will have been taken up by the acid solution, 
which will be indicated by the loss of weight in the precipi- 
tate. 
Phosphate of Lime. — We purchased, last year, an article 
under this name, which, on examination, proved to be little 
else than the carbonate of lime, that very useful and con- 
venient material, where any white powder is concerned. 
This article had been levigated and dried in flat and broad 
drops, rather more compact and brittle than the drops of 
Creta prseparata. 
Potassae Sulphas. — A quantity of sulphate of potass was 
sent to us, last year, more than one-half of which consisted of 
crystals of a greenish white color. On examination they 
were found to be contaminated with sulphate of copper. 
