336 



RECORD OF CURRENT RESEARCHES RELATING TO 



at the free end, whicli results 

 in its ineifectually passing 

 over the object (the latter 

 merely tilting it up), a screw 

 TO is inserted in the horizontal 

 plate of the knife - carrier 

 which serves to raise the 

 free end of the knife more 

 or less. The alteration of 

 angle caused by an elevation 

 of one end of the knife with- 

 out that of the other may be 

 compensated by a correspond- 

 ing inclination of the object 

 clamp. 



In theory the best posi- 

 tion for the knife is horizon- 

 tal, but in practice this has 

 the disadvantage that the 

 under side of the knife drags 

 on the surface of the object. 

 This can be remedied by 

 raising the back of the knife, 

 which can also be done by the 

 screw m. To clamp the knife 

 when set otherwise than in a 

 horizontal position, the ordi- 

 nary form of screw, with an 

 under surface of fixed in- 

 clination would, be useless ; 

 a spherical form is therefore 

 given to the under surface 

 of the screw n so as to fit 

 into a corresponding collar o 

 inserted between the knife 

 and the screw. The collar 

 can then be made to follow 

 the inclination of the knife, 

 and. is readily fixed by the 

 clamping screw. 



The third improvement 

 consists in the movement of 

 the object clamp by means of 

 a micrometer screw instead of 

 by the hand (Fig. 27). This 

 screw p as it turns in the 

 sockets q q inoves the piece r, 

 which is attached to x and the 

 latter by the screw w to the 

 object-carrier, so that each 



