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quantity of paraffin. It is important for the sides to be cut 
parallel in order to get the successive sections to stick together 
properly for forming a continuous ribbon. 
The razor blade by which the sections are cut is in the 
machine made a fixture, and the object to be cut is moved to 
and fro against the blade; instead of the object being stationary 
and the blade moved, as in section-cutting by hand. The use 
of this is to obtain a continuous unbroken series of sections 
forming a continuous ribbon, which passes across the blade, 
and is received upon a travelling band that moves forward 
at the same rate as the sections are cut, standing still during 
the return motion of the sliding block that carries the object 
back in preparation for the next cut. The object holder is 
supported by a screw of fine pitch which has a ratchet wheel 
fixed upon its head, and in each return stroke of the sliding 
block this ratchet wheel meets a catch which turns it round 
one or more teeth, according to the desired adjustment, and 
thus advances the screw to raise the object the thickness of 
the next cut. This can be adjusted so that the thickness of 
each section is uniformly 01 ‘ 2 oW h inch, or other¬ 
wise as may be desired. The driving wheel is either turned by 
hand, or it can be driven by power by means of a band round 
the circumference of the wheel. It is readily driven by hand 
at the rate of 100 sections cut per minute, and can be driven 
by power at a higher rate without difficulty, and the quick 
motion is advantageous to the perfect condition of the sections. 
For the mounting of the sections, the glass slide is first 
covered with a thin film of collodion, mixed with an equal 
quantity of oil of cloves, which is dropped on the slide and 
levelled by a needle held fiat across the slide, and stroked 
down its whole length. The ribbon of sections is cut into 
lengths to suit the slide, and the pieces dropped on to the 
slide, guided by a needle, in two or three rows, according to 
the width of the sections, and they adhere firmly upon the 
collodion film. The slide is then exposed to a uniform heat 
of 180° to 140° Falir. for half a day to soften the paraffin and 
make it readily soluble in turpentine, and the whole slide is 
then dipped endways into a bottle of turpentine, by which the 
paraffin is all dissolved oft’ at once, if properly softened. The 
slide is then mounted direct in balsam, by dropping on some 
balsam diluted with turpentine, and applying either a single 
cover glass of the whole length, or two or more square cover 
glasses to make up the required length. The sections remain 
quite fixed on the slide in the positions they were originally 
placed upon the collodion film, and there is no danger of any 
displacement or injury in the subsequent processes of the 
mounting. 
