THE CHEMISTRY OF THE HIVE. 
591 
now in comparatively small compass, should be placed 
in a canvas bag, along with a weight, and once more 
boiled with water, when it will yield almost all its wax 
if it be kneaded with a stick ; and this, left to slowly 
cool as before, will be scarcely inferior in quality to 
that first obtained. Mr. J. M. Hooker recommends 
that the combs be put into a copper, and pressed 
down as closely as possible. A hoop, just fitting the 
copper within, is covered with cheese-cloth, and is 
pressed down over the combs, and kept in place by 
sticks wedged against the ceiling, or other means. 
The copper is now filled with water, and, upon boiling, 
the wax will separate from the refuse, and, rising 
through the cheese-cloth, can be taken off, when cold, 
in a solid block. 
If tinned vessels are used for the melting, nitric 
acid must not be employed. Metal is undesirable 
with any acid, so that an excessive quantity should not 
be added; and if rain water be at command, it may 
be omitted. An iron vessel, made hot, and rubbed 
with any kind of fat, will not afterwards discolour 
the wax, as it is likely to do if this precaution be 
not taken ; nor will acids in moderate amount now 
affect it. Copper vessels are to be preferred. 
Those who desire a special appliance, will find the 
wax-extractor of Professor Gerster both convenient 
and effective. It fits, like an ordinary culinary 
steamer, over a large saucepan, and consists of a tin 
cylinder, within which is placed the perforated basket 
carrying the combs. Beneath is a circular tray, which 
receives the dripping wax, to be carried off by a 
spout passing through the side of the cylinder. The 
