CHAS. LENTZ & SONS 
LARGE LABORATORY MICROTOME— DESCRIPTION. 
A represents the slide piece with projecting arm B, from the end of which a 
heavy stud M projects downward. C is a quadrant pivoted to the lower side of 
the arm B and slotted to receive a stud projecting from the main feed lever H. 
The quadrant bears a scale one division of which corresponds to two divisions on 
the head of micrometer screw D and the edge is toothed to correspond with the 
graduations. The main feed lever H is pivoted at its proximal end at the same 
point as the quadrant so as to move with it when desired. 
It bears a pointer G, and a pawl E, which engages the teeth on the margin ot 
the quadrant, and the small lever, F, which controls pawl E. In use, F is brought 
to a central position on H, releasing E. E is then set at the graduation indicating 
the thickness of section desired, stop L being held against the stud M meanwhile. 
F is then moved to the right clamping E firmly in position, and at the same time 
causing the pawl I to engage the teeth of D. A movement of the lever H to the 
right will now cause the quadrant and also the micrometer screw to rotate until 
the stop U strikes the stud M, which is stationary. The distance moved will be 
equal to the arc indicated between zero on the quadrant and the graduation at 
which E is set. H being returned to the left until L strikes on M, I does not 
engage the teeth of D, and D is prevented by the - brake K from rotating back- 
ward. It will thus be seen that the feed being set, a simple movement from left to 
right elevates the object the exact distance required, without the possibility of 
going beyond the limit and raising it too much. 
All the movable parts of the Microtome should be kept as free from dust as 
possible, and well lubricated with dental or clock oil only. 
The knives furnished are hand-forged^ and are manufactured in our own 
workshops for Bausch & Lomb Optical Company, from the best English steel, 
and are guaranteed of the proper temper and hardness for microtome work. 
They are furnished properly sharpened for cutting, but, of course, should be 
gently stropped before using. Special care is taken in their manufacture, and 
each knife is thoroughly examined, tested and retested before leaving our 
factory. They are ground and polished by original and novel machinery, guided 
by trained mechanics, so that perfect straigfhtness and parallelism of the 
cutting edge, shank of knife, and bed are assured. The hardening is done by a 
special and expensive process. Our knives are not equalled by any of 
foreign manufacture. 
They are in use in a very large number of laboratories in all parts of the 
United States, and we have received several excellent testimonials from men who 
have had them in use for years. 
Wherever we have placed these microtomes we have invariably been informed 
that they are by far the best our customers have ever used. 
We have special facilities for accurately regrinding and honing microtome 
knives of any manufacture, shape or size, and would warn our customers from 
having microtome or other knives reground by inexperienced parties, as the hard- 
ness and temper of a knife can be ruined in a few seconds by an inexperienced 
workman, and it cannot afterwards be rehardened and is incapable of receiving a 
keen edge. 
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