Cutting 



PARAFFIN SECTIONS 



115 



on tlie hack of tlie inierotoiue is turned 

 until tlie block is as far back as possible, 

 and the entire knife is moved on its car- 

 riage until the edge of the blade is about 

 }i inch in front of the block. A last-miiuite 

 check is now made to make sure that the 

 divisions of the setting device exactly co- 

 incide with the thickness desired ; then the 

 handle is raj^idly rotated until the block 



in the left hand, is slipped under the rib- 

 bon which is then raised in the manner 

 shown in Fig. 65. Care should be taken 

 that a few sections always remain in 

 contact with the blade of the knife, for 

 if the ribbon is hfted till only the edge of 

 the section lies on the edge of the knife, 

 the ribbon will usualh^ break. As the 

 handle is turned, the brush in the left 



Fig. 66, Laying out the ribbon. 



starts cutting. The front face will rarely 

 be parallel to the blade of the knife, there- 

 fore a considerable number of sections will 

 have to be cut until the entire width of 

 the block is coming against the knife. No 

 particular attention need be paid to the 

 quahty of this initial ribbon, which may 

 be thrown away. 



We will assume that all is going well and 

 that the ribbon is coming off in a perfect 

 condition; if it is not, refer to Table 1. 

 The remaining operations of preparing 

 and mounting the ribbon are far more 

 clearly seen in illustration than by descrip- 

 tion. As soon as the ribbon is the width 

 of the knife in length a dry soft brush, held 



hand is moved away until the ribbon is 

 the same length as the sheet of paper on 

 which it is to be received. Legal size (fools- 

 cap) paper is quite commonly employed 

 and is shown in Fig. 66. Notice that the 

 left-hand edge of the ribbon has been laid 

 flat some distance from the edge of the 

 paper and that a loop, sufficiently large 

 to avoid strain on the ribbon attached to 

 the knife, is retained with the brush, wdiile 

 the ribbon is cut with a rocking motion 

 with an ordinary scalpel or cartilage knife. 

 The larger and colder this scalpel is, the 

 less likelihood there will be of the section 

 adhering to it. The purpose of leaving a 

 good margin around the edge of the paper 



