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VINEGAR.
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tub. The chips should be prepared for this
purpose, by being repeatedly scalded in boiling
water, then dried, and imbued with hot vine–
gar. The same rneasures rnay also be adopted
for the tub. To provide for the renewal of the
air, the tub is perforated at about a foot from
its bottom with eight holes, set equally apart
round the circumference, two-thirds of an inch
wide, and sloping down, through which the air
may enter into this lower compartment, with–
out the trickling liquor being allowed to flow
out. In order that the foul air, which has
become useless, may escape, four large holes
are pierced in the sieve cover, at equal dis–
tances asunder, and from the center, whose united
areas are rather smaller than the total areas of
the holes on the side of the ·tub. Into these
four holes, open glass tubes must be inserted, so
as to stand some inches above the cover, and to
prevent any of the liquor from running through
them. The proper circulation of the air takes
place through these draught holes. This air