COMBINATION FUNNEL SUPPORT AND BURET CLAMP PHILIP S. CHEN Nashville Agricultural Normal Institute, Madison College, Tennessee
THE ordinary wooden funnel support used in most chemical laboratories is quite bulky, and unlike some of the other pieces of laboratory apparatus, it serves
hut a single purpose. It occupies too much room on the table when in use, and takes up a large portion of drawer space when stored away. For these reasons, its use in the chemical laboratory is more or less limited to quantitative analysis work, which calls for frequent filtration operations, in each operation three or four funnels being employed simultaneously. For general chemistry laboratory work, which seldom calls for this operation and where one set of filtration is usually sufficient, the use of the ordinary bulky wooden funnel support is quite inconvenient. Consequently, instead of using the funnel support, the student generally resorts to the use of either iron rings or buret clamps. The use of the iron ring as a substitute is limited to large-size funnels only. For the ordinary size funnel, the iron ring is too large. On the other hand, the use of the buret clamp does not give satisfactory results. Since it has a loose grip on the funnel stem, which is often too slender, i t does not give a steady, rigid support to the funnel, and spilling of the solution from the funnel is frequently the result. Fortunately, this situation can be easily eliminated by a simple alteration in the construction of the buret clamp. By replacing the hand screw on the clamp with one that has a ring on the end, as shown in the figure, the buret clamp can be made to serve the additional purpose of a funnel support. The size of ring may be varied, but one of one and one-half inches in diameter is large enough for the ordinary 65-mm. funnel. The improved hand screw may he fastened to the clamp by riveting both the screw and clamp together. The funnel ring then becomes stationary.
