Figure 5 is a view partly in elevation and partly in section, the same being taken along y the line 55 of Figure 4. by numerals, 1 indicates a base which may be wood, bakelite, or other material, and which carries any desired number of posts 2, which may act as handles for supporting the de The tubular transverse casing 3 has one end closed and rounded, while the opposite end is open, and the wall