30 H. Goadby on making wet Preparations of Animal Substances 
by means of the crank d, the latter wheel, having for its axis @ 
spindle, e, the lower end of which screws into the brass mount 
of the copper drill, f, whilst its other end passes through a collar 
in the upper arm of the iron support and is regulated in its action 
by the wooden lever ¢. a} 
= 
by four nut-headed screws. h, h, are two thick pieces, of wood 
marked &, being beveled to the same angle, may freely move. 
In the center of the pieces marked & is a slit, through which 
passes a nut-headed screw to connect them with the lower board 
and to admit of their adjustment, their inner extremities are cut 
to form half a square and are intended to receive the block of 
glass pl diagonally, to be drilled by the machine. 
block of glass, J, should be placed exactly in the center, and t — 
can easily be secured in its position by clamping the side pieces 
of wood by means of the nut-headed screws and collars. 
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