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The fluid intended for distillation flows from the tube (s) into the funnel (p), thence into the vessel (A), entering its lower part, and serving to condense the alcoholic vapour. From this vessel the warmed fluid passes by means of the tube (r) into the lower part of the second vessel (B), where dephlegmation takes place by means of a condensing tube. From B the fluid flows through the tube (c) into the second still (C), which is heated by the hot gases evolved from the fire, kept burning under the first still (D); in the still (C) the fluid undergoes a rectification, and the vinasse flows by the tube (e) into the still (D); m is the pipe for conveying the hot vapour from D into C; the tube (b) carries the alcoholic vapours into the dephlegmator. The tube (d) conveys the phlegma into the still (C); g and h are glass gauging-tubes for indicating the height of the fluid in the interior of the stills; the tube (l) conveys the uncondensed vapours from the dephlegmator into the condensing apparatus, while i carries the vapours formed in the vessel (B) into the condensing apparatus.

The alcohol condensed in the cooling apparatus flows, as shown in the cut, into the vessel (o), provided with a hydrometer, which shows the strength of the liquid. The cooling apparatus of the vessel (B) consists of seven compartments or sections formed by wide spirals, to each of which, at its lower level, is attached a narrow tube, all of which tubes are connected to the tube (d), which latter conveys the condensed fluids back into the still.

A very simple form of apparatus in use is that figured below.

A is a cylinder made of cast iron or copper, in which the fluid to be distilled is heated by a spiral tube made of copper. The inlet of this tube is shown at b and the outlet at a.; c serves to carry off the vinasse; B is the dephlegmator, through which the fluid to be distilled continually flows in a downward direction, while the vapour of the low wine evolved in A ascends uninterruptedly.

The dephlegmator is so constructed as to have as large a surface and as many points of contact as possible. The vapour ascends to the reservoir (E), and passes into the rectifier (C) by the tube (F). The condensed portion returns through the tube (H) to the dephlegmator, whilst the uncondensed vapour passes on to the condenser of the vessel (D), where it becomes condensed, and is carried off through M. The liquid intended for distillation is kept in a tank (not shown in the engraving), placed above the apparatus, and is conveyed to the latter by the tube (L I), fitted with the stop-cock (K), so that the liquid arrives first in D, is next conveyed to C, thence through G into the dephlegmator, and finally into the cylinder.

Divers adaptations for heating by steam have been arranged, in a very convenient form, by Mr Coffey. His so-called Esculapian still affords the pharmaceutical chemist the means of conducting the processes of ebullition, distillation, evaporation, desiccation, &c., on the small scale. The following cut represents his apparatus.

B, a burner supplied with gas by a flexible tube; C. the boiler or still; I, an evaporating pan fixed over the boiler, and forming the top of the still head; K, a valve for shutting off the steam from I, when it passes through the tube (M), otherwise it would pass through L, and communicate heat to the drying closet (O O), and from thence to the condenser (T T). o is a second evaporating pan over the drying closet.