Q, draws the arm b down, and thereby holds up n ; e therefore remains open. Byrods on the back wall t, t, the hook i, in which n' rests, proceeds from /. When u
is raised R sinks. The catch, c b, enters with its front tooth into a slanting notch uponthe upper edge of n, spontaneously by the action of the spring e ; whereby the open-ing e, is shut. The small door, N, rises again with the front arm of the leverby the operation of the weight Q of itself, as soon as the catch is released by pressureUpon c.
The most important part of the whole apparatus is the drum, k, for the reception
and rounding of the bits of glass. It may be made of strong copper, or of hammered
or cabt iron, quite open above am;pierced at the bottom with a squarehole, into which the lower end ofthe long rod, t, is exactly fitted, andsecured in its place by a screwedcollector nut. The blunt point, x,(Jig. 114) rests during the work-ing in a conical iron step of thelaboratory, Jig. 115. On the mouthof the drum, k, a strong iron ringis fixed, having a bar across its di-ameter, with a square*hole in itsmiddle point, fitted and secured bya pin to the rod t, and turned byits rotation. The vessel k, and itsaxle, 1, are laid in a slanting direc-tion ; the axle rests in the upperring, z, at the lower end of therod, /, of which the other end ishung to the hook, n, upon themantel beam, n. On the upper endof t, the handle, s, is fixed for turn-ing round continuously the vessel,K, while the fire is burning in thefurnace, the fuel being ppt not onlyin its bottom chamber, but also intothe holes, f, a (fig- 114). Thefire-wood is made very dry beforebeing used, by piling it in logs uponshown in figs. 114, 115.
t( >e iron bars, 9, 10, 11, under the mantelpiece, as