Photomicrography 209 



studied with a fine binocular research microscope, and it becomes 

 desirable to photograph a loose floating cell that is in satisfactory 

 orientation. It is impossible to remove the slide from immersion con- 

 tact with the objective and condenser, transport the slide to another 

 part of the laboratory or another part of the city, set up the slide on 

 another microscope, and locate the specific cell and photograph it 

 in the original condition. Even if a permanent slide is used, the 

 investigator — who is the only one who knows what is wanted — must 

 personally locate the desired field and focus at the desired level. 



These conditions call for equipment that permits a quick change 

 from critical visual work to photomicrography, right in the research 

 laboratory. A step in this direction is the use of a commercial metal 

 base on which the microscope and the lamp are permanently fastened 

 and aligned (Fig. 17.3) . This arrangement can be used with attach- 

 ment cameras that ride on the microscope, as well as with a more 

 rigid pillar camera. This arrangement permits comfortable visual 

 study and a quick change to photography. The camera can be 

 removed and used by another worker who has a similar private base, 

 microscope and lamp. The versatile Spencer apparatus in Fig. 17.4 

 permits quick change-over from visual study to a 35-mm. or 4-by 5- 



FiG. 17.5-Bausch & Lomb reflex camera that permits maximum versatility for visual 

 study and photograpliN, with Micro Tessar lenses as well as with all powers of the 



compound microscope. 



