INDEX 



A 



Achromatic objectives, for visual purposes, and 

 also those corrected for photography, 78, 



19, 117 

 Adjustment, cover-glass, 84 

 Albumen prints, mistakes in making, 45 

 Amphipleura pellucida, how to photograph, 140 

 Angle, " critical," 83 



" limiting," 83 

 " Annular light," danger of misinterpreting results 



obtained by the use of, 94 

 for illuminating objects placed on microscope, 



112 



" Antihalo " plates, their use in photo -micrography, 

 20 



Apertometer, by Zeiss, 88 



Aperture of condensers, A Note on, 89 



numerical, what is it ? 85 



numerical, how obtained bv apertometer, 88, 

 89 



how obtained by method of Conrady for dry 



objectives, 90 

 Apochromatics, table of penetrating power, 129 

 Apochromatic objectives, 80, 116, 117 

 Author's arrangement for producing annular light, 



95 



photo-micrographic stand and apparatus for 

 medium and high power work, 54 



arrangements for low-power work, 14, 24 

 27 



Auxiliary condenser as arranged by author, 104 

 condenser, its position, 54, 104 

 . condenser, how to centre, 105 



Auxiliary condenser, 104 



condenser as arranged by "Watson, 104 

 condenser, its use and objections discussed, 

 104 



front, for use with camera in low-power 

 photo-micrographs, 19 



B 



Backing plates in photo-micrography, 20 

 Bacteria, photography of, 134, 143 



the use of contrast screens to make good 

 photographs, 145 

 Baker's photo-micrographical stand, 49 



microscope, Kelson model, 60 

 Beard's jets for mixed gas, 5 



gas-bottle regulators, 9 

 Beck's model for photography, 61 



objectives, 78 



photo-micrographical table, 49 

 Blow-through jet, 7 

 Board of Trade and gas-cylinders, 8 

 Brewster, Sir David, his view of use of substage 



condenser, 95 

 Brin's oxygen works, 8, 137 



cylinders the best that can be used, on account 

 of the firm's many experiments for produc- 

 ing absolute safety, 8 



0 



Camera and microscope, excluding light from their 

 junction, 1 18 



