36 
Stand for Photo-micrography. Square stage, looxioo 
mm (4" X with mechanical stage for imparting delicate move- 
ments to the object- slide, which may be of any size (inch cultiv- 
ation plates). 
Body very short and of great diameter, so that photographic 
objectives of very long focus (projection system 70 mm) may be 
used within it. 
In all other respects similar to stands I and r\ 
This stand may, with good adyantage, he used for usual 
ocular ohseryation. 
For the purposes of photo-micrography it is advisable — and 
for all advanced work necessary — to substitute for the usual 
condenser of 1.40 aperture the achromatic centering con- 
denser of 1.0 aperture, price M. 75. — (No. 20). This condenser 
may, naturally, be used for ocular observation as well. 
The mechanical stage of the above stand is constructed 
with a view to imparting such a very slow motion to the object 
as the projection of a magnified image at a great distance ne- 
cessitates. Whilst the revolution of the object is effected in the 
ordinary way by turn-table rotated by rack and pinion, the cross 
motions are obtained by two sliding-pieces mounted at right angles 
to one another and actuated by micrometer screws. Vernier reading 
to 0.10 mm as in stand I''. 
With Abbe illuminating apparatus No. 17 with ordinary (non- 
achromatic) condenser of 1.40 apert 
Achromatic centering condenser No. 20 
Or id. non- centering and without iris diaphragm, inter- 
changeable with the usual condenser 
The prices of stands do not include any optical or mechanical parts beyond 
those enumerated in the above specification. Suitable combinations are com- 
piled at the end of the_ catalogue. 
