710 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
Treatment of a knife-blade which has first been sharpened by Vienna 
lime with either of these powders for a few moments suffices to give to 
the edge the extremely small notches necessary in order to prevent the 
pressing together of the sections. 
For the preparation of celloidin sections a very obliquely set knife, 
which must be kept moistened with alcohol, is required. For this 
purpose, therefore, the form of the knife-holder and object-holder are 
modified as shown in fig. 106. The knife-blade is clamped above and 
Fig. 106. 
below. The upper clamp a is carried by a vertical rod, the under b is 
attached to the base of the flat reservoir c, and is adjustable in the hori- 
zontal direction. Both clamps are provided with screws by which the 
inclination of the knife can be regulated. 
The knife-holder (fig. 106) is fastened to the microtome by the • 
screw d. Beside the reservoir c there is a second one e more to the 
right, which serves to protect the instrument from the alcohol which 
is allowed to drop upon object and knife during the cutting. 
The reservoir e in which the sections are collected is at first filled 
with alcohol, which is kept at a constant level bv means of the exit 
tube g . 
