and Laboratory Methods. 



1995 



notches indicated by wheel J. If, however, one desires to cut sections 5 micra 

 thick, then only the dog E and ratchet wheel A are needed. Dog F is thrown 

 out of play by the prop E, and the gear wheel C is moved back out of play with 

 gear wheel A. This is done by an eccentric device shown in Fig. 2. The 



Fig. 1. 



spindle D, on which the gear wheel C and ratchet B run, is eccentric on the 

 shaft O. By means of the lever L this shaft is turned in its support N so that 

 the gear may be readily thrown into or out of play. The shaft O may be held 

 in any position by the thumb-screw M. 



It is thus readily seen that this attachment is very little more complicated 

 than that of the ordinary Minot, and is just as compact. 



One objection is to be raised to it. One can cut sections ranging from 1 to 

 5 micra, but after that it must be 10, 15, 20, or 25 /<. That is, there is no inter- 

 mediate thickness between 5 and 10 /<, etc. This might be obviated by making 

 the notches of A smaller so that they would equal 3 //, or 

 even less. The author has not found the 

 above objection a serious drawback, and 

 believes it of little importance. 



A photograph of the machine show- 

 ing the attachment is seen in Fig. 4, 

 which shows the general appearance. 

 Yjq 2. A device for holding the microtome pic. 3. 



