142 



SUMMARY OF CURRENT RESEARCHES RELATING TO 



graphs on paper copies or glass positives (which is important in the 

 case of stereographs), the opening at C has two cuts in its margin 



Fig. 30. 



which show on the plate as two small black lines (see H) and so 

 enable the image to be easily oriented. 



Dr. A. Moitessier's camera,* B, fig. 31, is intended for taking six 



Fig. 31 



micro-photographs, each aperture having a sliding shutter A. Being 

 too heavy to be supported on the Microscope, a special support for it 

 is necessary, fig. 32. The camera C is placed on the wooden plate B, 



* ' La Photographie appliquee aux recherches micrographiques,' 1866, p. 121. 



