708 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
flywheel r. On this axis to the left is the crank s by which the up and 
down movement of the slide m with the paraffin block is produced. On 
the same axis more to the right is the excentric disc t , the rotation of 
which effects the movement of the toothed-wheel h. By means of the 
rods u u and the axle v, the piece w is moved by each rotation once up 
and down. By the pressure of a spiral spring the two pawls attached to 
w engage in the teeth of the wheel h on the ascending movement, but 
Fig. 105. 
glide over them, since they are pointed obliquely downwards, in sinking. 
The left pawl can be slightly raised by a screw and thus put out of 
action. Both pawls are regulated by the segment x which is adjusted 
on the main axis by the screw y. It allows of a displacement of the 
knife up to 40 microns. The capability of adjustment of the left pawl 
enables displacements of 1/2, 1J, 2^, &c., microns to be made. Thus by 
making the left pawl shorter by half a tooth and adjusting the right 
pawl by the segment x to half a tooth, the two pawls will act alternately 
in raising the wheel by half a tooth. 
The length of the micrometer-screw on the main axis is 3 cm. 
