90 
ORIGINAL COMMUNICATIONS. 
a rough section of which I subjoin. This jar should be rinsed 
with boiling water before each time of using, to avoid loss of 
heat as much as possible; the ingredients to be infused are 
then to be placed upon the perforated plate, and boiling water 
poured over them; employing a vessel of such dimensions 
that the required quantity may sufficiently overtop the ingre- 
dients after allowing for the portion likely to be absorbed. 
During the maceration, the contiguous fluid becoming charged 
with soluble matter, sinks through the perforations, and un- 
saturated water will supply its place as long as any thing fur- 
ther remains which water has the power of dissolving. It is 
of great advantage to maintain the maceration at a gentle heat, 
which is readily accomplished by placing the vessels upon a 
heated plate near the fire, as the top of an iron oven, &c. &c, 
which also renders convenient the application of my mode of 
preserving them. This consists in the removal of atmos- 
pheric pressure, and with it the greater part of the air, gene- 
rally present in a state of diffusion or solution in the water, 
by which the seeds of the cryptogamous byssi, or mould, 
which commonly form in infusions, are developed and sup- 
ported. With this view, when the maceration has continued 
the time prescribed, the infusion should be strained while hot, 
and immediately transferred to bottles, provided with ac- 
curately ground stoppers, which are to be made perfectly full; 
allowing the stopper to displace its own bulk of the liquid. I 
secure the stoppers from being mismatched by tying each to 
its own bottle by a piece of string of convenient length. As 
the infusion cools, a partial vacuum is formed by its contrac- 
tion, which is the more complete the higher the temperature 
at which it is bottled, and the freer the infusion from diffused 
air. The same object may be effected by the use of a com- 
mon bottle and perforated cork, closing immediately the aper- 
ture from which the displaced fluid escapes, by sealing it with 
sealing-wax. On this principle I have for several months pre- 
served my infusions with great facility and advantage; and 
by the latter mode, with corks, I preserved Infusion of Cus- 
paria from the fourth month, (April,) of last year until with- 
