INDEX. 



ADVANTAGE of pure hydro- 

 gen, 69. 



Aniline colours, 161. 

 Aphengescope, 246. 

 Astrometeoroscope, The, 180. 



BELL, Electric, 271. 

 Biunial, Detachable, 13. 

 Biunial lantern, 8. 

 Blow-through jet, 53. 

 Boards, Double, 62. 

 Brass work, Superfluous, 10. 

 Brewster, Sir David, 5. 

 Brin's Oxygen method, 46. 



CAMERAS, Detective, 260. 

 Camera for microscope, 215. 

 Cameras, Hand, 259. 

 Capacity of cylinders, 49. 

 Carriers, 250. 

 Cellini, 1. 

 Choreutoscope, The, 180. 



Clamp, Steward's, 56. 

 Clouds, 164. 

 Clouds, Printing, 233. 

 Cohesion figures, 175. 

 Collodio-bromide process 111. 

 Colosseum, 1. 

 Coloured gelatine, 188. 

 Colouring lantern slides, 145. 

 Colours, Complementary, 166, 



188. 

 Colours used for slide painting, 



149. 

 Complementary colours, 166, 



188. 

 Compound frame for copying, 



126. 



Compressed oxygen, 48. 

 Condenser, Dallmeyer's, 23. 

 Condensers, 21. 

 Copying apparatus, 124. 

 Copying paper prints, 121. 

 Current reverser, 173. 



