CHAS. LENTZ & SONS 
flttacDaDk Wecbanical Stage 
NEW CONSTRUCTION 
FOR BB OR OTHER STANDS 
The difficulties encountered by manufacturers in making mechanical stages 
have been not only in the line of producing a stage perfect when it leaves the fac- 
tory, but which will retain its delicate adjustment after a period of wear. 
In our opinion every microscope for individual use should be equipped with 
one of these stages, as they are now both durable and inexpensive. The Stage 
is attachable to any, except the very smallest Stand* Any one may easily apply 
it to the microscope by simply following directions accompanying it. When 
ordered with the microscope, a special device is applied so that the stage may 
be removed, and replaced in exactly the same position. 
The rectangular movements are both by rack and pinion, as all efforts to pro- 
duce a perfect worm-screw movement have been unsuccessful. The rack and pinion 
is preferable, as it is perfectly reliable as to wearing qualities, is more sensitive 
than the screw, and gives equal speed in both directions. Millimeter graduations 
with verniers are attached to both movements. The object carrier is so arranged 
that the shde rests upon the surface of the microscope stage and may be used in 
immersion contact with the condenser if desired. 
The stop against which the slide rests is adju.stable, permitting the use of slides 
of various sizes. The object carrier has an extraordinary range, the movements 
being 35 and 60 mm. respectively. 
The stage is held in place on the microscope by a solid metal clamp, open at 
one side, which slips upon the base washer of the arm of the microscope in such a 
manner that the simple tightening of the thumb screw at the back locks it immov- 
ably. The clamping: device may be left attached to the microscope permanently 
and the object carrier removed by simply racking it out of the slide. This feature 
is of great value, as the Mechanical Stage is necessary for search work, counting, 
etc., while an unobstructed stage is required when examining colonies of bacteria 
in Petri dishes, using watch glasses on the stages of the microscope, etc. 
This mechanical stage is of the utmost value in searching for tubercle bacilli, 
casts, etc., when there are few in the specimen, or for use with the hsemacytometer 
for counting blood corpuscles. When a particular object or field is found (even 
with the xV objective) and its position noted with the vernier, it can be found again 
after thoroughly searching the specimen for others. 
Attachable Mechanical Stage, in velvet-lined Morocco Case $18 00 
* When ordering this stage for microscopes other than Bausch & Lomb's make, kindly state ; 
a, distance from center of arm to center of stage ; d, distance from top of stage to bottom of 
arm washer ; c, height of arm washer ; d, diameter of arm washer ; e, diameter of arm. If for 
one of the older instruments, give serial number of the instrument. 
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