1024 General Notes. [ October, 
process. of cutting; and this appears to me to form another se- 
rious objection to the instrument. 
The construction of the instrument is as follows: Two up- 
rights are cast on the base plate of the instrument, and are pro- 
vided with slots at the top, into which the razor is placed and 
clamped by two screws with milled heads. 
The imbedded object is cemented with paraffine into a brass 
tube which fits tightly on to the end of a cast-iron lever. This 
tube can be made to slide backwards or forwards so as to bring 
the imbedded object near to the razor ready for adjusting. The 
cast-iron lever is pivoted at about three inches from the end of 
the tube. To the other end of this lever is attached a cord by 
which the motion is given and the object to be cut brought 
across the edge of the razor. The bearings of the pivot are V- 
shaped grooves which themselves form part of another pivoted 
system. 
Immediately under the first pair of V’s is another pair of in- 
verted V’s, which rest on a rod fixed to two uprights cast on the 
base plate. A horizontal arm projects at right angles to the 
plane of the two sets of V’s, the whole being parts of the same 
casting. On the end of the horizontal arm is a boss with a hole 
in it, through which a screw passes freely. The bottom of the 
oss is turned out spherically, and into it fits a spherical nut 
working on the screw. The bottom of the screw rests on a pin 
fixed in the base plate. : 
It will be seen that the effect of turning the screw is to raise 
or lower the end of the horizontal arm, and therefore to move 
backwards or forwards the upper pair of V’s, and with them the 
lever and object to be cut. The top of the screw is provided 
with a milled head, which may be used to adjust the object to the 
cutting distance. í 
- The distance between the centers of the two pivoted systems 15 
one inch, and the distance of the screw from the fixed rod is six 
and a quarter inches. The thread of the screw is twenty-five to 
the inch ; thus if the screw is turned once round, the object to 
I 
be cut will be moved forward 3: of 617 or rte of an inch. 
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