III.--TRITURATING APPARATUS.
The apparatus hereafter described is in general use, and was invented by Herr Paul Grundner, of Berlin. It is particularly adapted for finely dividing large quantities of emulsion. It consists essentially of a wooden lid, a b, fitting upon a large stone pot, to the under side of which two strong trapezoid pieces of wood, e d and e f, are fixed, in the under part of which semicircular incisions are cut and held together by two leather straps, supporting a strong, easily-removable iron transverse bar, g h. Through the center of the lid, and turned by the crank, m, passes the axle i, which ends under the lid in the long ring, n.
The stiffened emulsion is then placed in the bag, o p q r, made of fine but strong canvas, with meshes about 0.5 mm. (such as is used for working upon with Berlin wool). The iron rod, g h, is then slipped through the four loops at the bottom of the bag, the open end is slung upon the ring, n, and bound tightly to it by the ribbons, r1. The loops upon the iron bar are then pushed as close together in the middle as possible, and the stone vessel is filled with water until o p q r is completely covered. The crank is then turned, by which the bag is wrung, and the emulsion squeezed through the meshes immediately into the water. When this process is continued until the purse between n and g h feels like a metal rod, the best part of the emulsion has been squeezed through, and if one now take out the bag and dissolve its contents, it will be found that the loss of emulsion is almost nil.
FIG. 2.
It may be remarked that the whole apparatus, with the exception of the crank, must be coated with asphalt varnish; also that the corners, r and q, must be separated off from the purse, as shown by the dotted line, s s s s, otherwise the emulsion would lodge there without being squeezed through. Instead of g h a strong glass rod may be used for small apparatus; but for large apparatus it is indispensable, as the power that requires to be exerted would be far too great for glass.