262 
PHARMACEUTICAL MEETING. 
Mr. Tilden said he had not tested the syrup for hydriodic acid, as he had 
not expected to find such a result. 
Dr. Redwood said there was a change which he had observed more than 
once in syrup of iodide of iron, which might be referable to the presence of hy¬ 
driodic acid. He had found that sometimes the cane sugar of the syrup passed 
into the state of grape sugar, the syrup at the same time becoming a solid mass 
of acicular crystals in consequence of the smaller solubility of the grape sugar. 
Mr. Hills had found the syrup made according to the Pharmacopoeia to keep 
without any change for several months. He supposed the change alluded to by 
Dr. Redwood had occurred after keeping the syrup for an unusually long time. 
Dr. Redwood replied that his observations had been made on specimens 
which, like most of the specimens in their collection, had been kept for several 
years. 
Mr. Umney described the way in which he was accustomed to preserve 
syrup of iodide of iron, by putting it while hot into bottles filled so as to exclude 
air almost entirely. In this way he found it to keep unchanged for six months 
or more. He had tried the coil of iron wire, but had not found any advantage 
from it. 
Mr. Carteighe stated that by simply immersing the bottle of syrup in a 
water-bath for a few minutes, the coloured syrup would be restored to its normal 
condition. He had frequent opportunities of seeing this simple operation suc¬ 
cessfully performed, and it was sometimes useful when the syrup was wanted 
quickly, and there was no time to make a fresh supply. 
Mr. Roberts corroborated the last statement. He had frequently found 
that colour could be quickly removed from the syrup by warming it. He could 
also confirm Mr. Umney’s statement. He believed if the bottles were well 
filled and kept in the dark no change of colour would occur. 
ON THE ADULTERATION OF WHITE PRECIPITATE. 
BY J. BORLAND, M.P.S. 
The paper submitted to the British Pharmaceutical Conference at Dundee by 
Mr. Barnes leads to the very gratifying conclusion that the substance above 
named is now to be found in commerce, comparatively free from those adulte¬ 
rations to which, in former times, it was frequently subjected; that it is now 
rarely, if ever, mixed with sulphate or carbonate of lime or lead to suit the 
demands of “country customers,” or supply the wants of druggists situated in 
localities where it might be considered that quality imported but little. There 
is a point, however, connected with the salt in question, to which Mr. Barnes 
seems not to have directed his attention. 
He has not informed us how many of the numerous samples that he exa¬ 
mined contained really white precipitate of the London or new British Phar¬ 
macopoeia. 
It is well known that there are two varieties, if we may so speak, of this ar¬ 
ticle of the Materia Medica, called respectively fusible and infusible white pre¬ 
cipitate. 
The British Pharmacopoeia, and its predecessors, the Dublin Pharmacopoeia, 
1826, the London Pharmacopoeia, 1836, and the Edinburgh Pharmacopoeia, 
1841, all adopted the formula which gave as a product infusible white precipi¬ 
tate, so that no other kind now is, or for a long time past has been, officinal. 
Prior to 1826, no formula, I believe, was given either by the Edinburgh or 
Dublin Pharmacopoeia for its preparation ; and the one adopted by the London 
Pharmacopoeia yielded what is now called by way of distinction fusible white 
