394 
PHARMACEUTICAL MEETING. 
caution, I think the following treatment good. Throw the sand into a large 
pan of water by degrees, stirring well; when all is in, allow it to settle, and de- 
caDt the liquid as close as possible ; then add some dilute hydrochloric acid, and stir 
the mass well; add some more water, stir and decant, and again drop the sand 
into water; collect and dry. By one manipulation sufficient of the insoluble 
ingredient may be prepared to last a chemist some considerable time ; but, prac¬ 
tically speaking, silver-sand is quite pure enough without this, and if there was 
any demand, would be sold ready-prepared by the wholesale druggists. 
In making my experiments, I used various quantities of sand, with an aim to 
find out the smallest quantity available in any one set of ingredients to render 
them in the best state for operation. In most cases I found twice as much sand 
as the weight of the dry ingredients of the tincture to answer very well, but in 
a few cases a larger quantity was required. The following is the form of appa¬ 
ratus I have used, and which I find possesses several advantages over the other 
forms already in use. There are now commonly in use two kinds, one of glass 
and the other of earthenware. The former has several disadvantages; it is very 
easily broken, and when broken there is some trouble to get it replaced. To get 
at the liquid the upper vessel has to be lifted off at a certain amount of risk, and 
then it is a most difficult thing to clean it; while its only advantage is that you 
can see what is going on, and this is practically of no great use. The earthen¬ 
ware ones at present in use are very unsightly, and have the same disadvan¬ 
tages as the glass, except that they are not so readily broken ; but for my per¬ 
colator I claim these advantages :—first, it is not an unsightly object; it can be 
most readily cleaned out, as there are no sharp angles in its construction ; all the 
process is conducted inside one vessel, and in its own atmosphere ; it is not so 
likely to be broken while cleaning or in use ; hot water can be used, so that it 
can be applied to the manufacture of infusions or extracts by percolation (of 
which subject I am not now treating) ; it can be used to filter anything through, 
and for a variety of other purposes; while, if one part gets broken, it can be re¬ 
placed by others, for they would be made in different sizes, known by quanti¬ 
ties, and each size would be moulded, by which means a stock would always be 
kept by the proprietors ready to fit; and I am assured, on good authority, that 
if made in quantities, they could be made sufficiently cheap to enable the manu¬ 
facturers to supply them to the trade at little more than half the cost of those at 
present in use, thus meeting the wants of the chemist by providing a cheaper 
and more useful article. This one I have before me is but a model, being 
