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interposed copper plates, in a similar manner to thatjust described. There are fifteen chambers in thiscolumn, the lower ten, k k k, &c., constitute therectifier, and its diaphragms are perforated andfurnished with valves and dropping pipes, preciselysimilar to those of the analyzer. The upper fiveform the finished spirit condenser, and are separatedfrom the other ten by a copper diaphragm, withoutperforations, but having a large opening at w, forthe passage of alcoholic vapour, and a dropping pipeat s. Round the opening, w, is a neck, rising aninch or so above the surface of the diaphragm,
which prevents the return of any finished spirit bythat opening. Under the dropping pipe, s, is a panmuch deeper than those of the other dropping pipes,and from this pan a branch pipe, ?/, passes out ofthe apparatus and carries the condensed, but stillvery hot spirits, to a worm, or other refrigerator,wherein they are cooled. The chambers, v v v v v,of this spirit condenser are formed of plain unper-forated diaphragms of copper, with alternate openingsat the ends, large enough both for the passage ofthe vapour upwards and of the condensed spiritdownwards; the use of these diaphragms being
Fig. 11 .
f|il t
merely to cause the vapour to pass along the pipe,m m, in a zig-zag direction, and to be thus moreperfectly exposed to its condensing surface.
In every chamber, both of the finished spirit con-denser and of the rectifier, is a set of zig-zag pipes,placed as shown in the plan, Fig. 12. Each set ofthese pipes is connectedwith the others by thebends, l l 11, thus formingone continued pipe, m m,leading from the washpump,Q, to the bottom of therectifier, whence it finallypasses out, and rising up,enters the top chamberof the analyzer, where itdischarges itself at n'. Mis the wash charger; L, asmaller wash vessel connected with it and with thewash pump. This vessel is called the wash reservoir;its use is to retain a sufficient reserve of wash, toprevent the apparatus being idle during the delay,which the excise regulations render unavoidable,between the emptying of the wash charger and therefilling it from a new back.
The pump, Q, is worked continuously during thedistillation, so as to supply the apparatus with aVOL. i.
regular stream of wash. It is so constructed as tobe capable of furnishing somewhat more than isnecessary, and there is a pipe, n, with stopcock, bywhich part of what is pumped up may be allowedto run back, and the supply sent into the apparatusregulated.
The steam from the boiler A is conveyed into thebottom of the spent wash receiver by the pipe, b b,which, after entering the receiver, branches into anumber of small pipes, perforated with holes. Thesteam is thus dispersed through every part of thewash in which the pipes are immersed. These per-forated pipes are not shown in the drawing.
When commencing an operation the wash pumpis set in motion to charge all the zig-zag pipes, m m m,until the wash passes over into the analyzers at n'.The pump is then stopped, and the steam let intothe bottom of the apparatus by the pipe, b b. Thesteam passes up through the chambers, b" b / , and bythe pipe, z, into the analyzers, whence it descends,through i, to the bottom of the rectifier at n. Itthen rises through the chambers, kk, enveloping thezig-zag pipes, and rapidly heating the wash con-tained in them. When the attendant perceives, byfeeling the bends, 11 /, that the wash has been heatedin several layers of these pipes, perhaps eight or tenlayers (the number is not of much moment), he
11
Fig. 12.