1868 The complete Practical Distiller

55

CONTINUOUS DISTILLATION.

Fig. 8.

Fig. 9.

number of the plaits, between each of which (as in ^g. 8) a ledge is run from side to side of the still, and fastened to both, leaving a passage the whole length underneath, be- tween its lower edge and the bottom of the groove formed by the plait, by which the liquid in its whole course is re- duced to a stratum of any thickness required along a surface of immense extent, occupying comparatively but a small space, and exposed to all the heat of the fire. In the fore- going descriptions the stills have been considered as in im- mediate contact with the fire ; but it is proposed to work them by steam, which may be applied either externally or internally, or both, as shown in fig. 10. In this figure, a represents a steam-boiler, furnished with safety-valves, and supplied with water in the usual way : this boiler is surmounted by three stills upon the foregoing principles. The bottoms are perforated at certain distances through- out their whole extent, and into each of these perforations a tube is inserted, branching into ramifications of smaller