MANUFACTURE OF ACETATE OF LIME. 
53 
Above this drying space another is formed by means of the chim- 
ney. The heat passes as well under as above the drying space, and 
passes into the chimney, which is situated at the side of the furnace, 
and can be shut by a valve, In the drying space the temperature 
is usually between 60° and 90° R. (167° to 2Mi° Fah. 
Turf forms the best material for fuel, as it does not burn rapidly, 
and produces a steady and equal temperature. 
Drying of the Acetate of Lime. — When the furnace is thoroughly 
and equally heated, the flame of the fire is allowed to subside. If 
wood is employed as fuel, the sliding door should be opened at the 
commencement in order to allow the moisture to escape. The salt 
is transferred from Ihe evaporating vessel to the drying plate, and 
spread out to the depth of two inches ; and after the first portion 
has become somewhat dry, the depth is increased to four or five 
inches, the heat is preserved at the degree already mentioned, for 
twenty-four hours, and during this time the salt is turned several 
times. Subsequently, when the mass appears to be becoming dry, 
the temperature may be increased to 100° (257° Fah.), so as to dry 
it completely. The mass is dry and properly roasted when it pos- 
sesses the following characters: — It must, before cooling, be brittle ^ 
easily crumbled between the fingers, mixed with blackish carbona- 
ceous points or streaks, between which appear white pieces of dry 
salt. A solution of the comminuted salt, in four or six times its 
volume of hot water, possesses a yellowish brown color with a dark 
tinge, while previously it had a reddish brown color. When the 
heat is increased towards the end of the process, as described, care 
must be taken to do it gradually so that no smoke shall rise from the 
acetate, because it might thus be decomposed. Neither must any 
spark be permitted to come in contact with the acetate of lime ; be- 
cause, like sugar of lead, it possesses the property, in these circum- 
stances, of catching fire and burning — by which the whole dry pre- 
paration would be completely destroyed. The treatment of the 
acetate of lime in this manner, by means of gradual drying, as ex- 
perience has shown, possesses many advantages over the method of 
drying the salt in an open vessel; because there is no loss of acetic 
acid, as always occurs by the latter process. The operator has the 
preparation completely in his power, and with little expense of fuel 
and time, many hundred weights of salt can be prepared at once. 
This process does not merely extend to the removal of the moisture 
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