THE PHOTO-MICKOGKAPHIC CAMERA 121 



long-extension ordinary photographic camera can then be 

 clamped on to this with a suitable clamping-screw, and can be 

 raised or lowered into any required position. The microscope is 

 placed underneath the camera, the image being projected upwards 

 on to the ground-glass focussing-screen. Such an arrangement 

 admits too of easily photographing large objects that do not 

 require a microscope at all, and yet that readily come within 

 the purview of a photo-micrographer. There are again many 

 objects, such as bacteriological tubes and plate-cultures, which 

 at times require to be photographed, and which may be much 

 more conveniently dealt with if they are lying flat down than 

 if they have to be supported in front of a camera in a 



FIG. 42. Simple form of Horizontal Camera. (J. Swift & Son.) 



horizontal position. This simple support enables most objects 

 of this nature to be easily dealt with, and it is also available 

 for low- or moderate-power photo-micrographic work when 

 required. 



Horizontal Cameras. Of the horizontal types of apparatus, 

 Fig. 42 is an illustration of the simplest possible form. Here 

 an ordinary plano-convex collecting-lens, microscope, and 

 camera, are simply placed on a wood base in their correct 

 relative positions ; no arrangement is made for ensuring that 

 they are in correct alignment or for enabling them to be re- 

 placed should either of the parts for any reason be removed. 

 Obviously this arrangement is of a very simple description 

 and has little to recommend it for other than the most 

 elementary work. Such an apparatus would usually be im- 

 provised by the worker out of an ordinary long-extension 



