Tow, such as brewers use for the nitration of malt liquor, answers well as a filtering medium for viscous fluids. The filtration is expedited by heat, and may lie accomplished in the following simple manner. Two funnels are necessary. One funnel is placed inside the other, an indiarubber plug being on the neck of the inner funnel, around which tic outer funnel fits. In order that the filtering liquid may be covered, the top of the inner funnel projects somewhat. The tow or paper is placed in the inner funnel, and the interspace contains water, which is kept hot by steam. which passes into it from a flask. The excess of water may be drawn off by means of a constant level syphon, or a strip of web-tape hanging over the outer funnel. The diagram is thus explained: - A is the outer funnel, which contains water, and into which steam is passed for heating purposes; B, inner funnel for filter; C, flask containing water: D, flask to collect filtrate; E, glass tubing tsteam from C is passed along the tube to A); F, burner to heat flask; G, tripod stand to support flask.

Filtration of Oils by Heat.