234 SEC. 7. LIGHT. 



928m. Two Sheets of Talbotype Prints from waxed 

 paper negatives. Robert Sabine. 



928n. Two Views for the Reflecting Stereoscope; 



the varnish used to render the prints transparent, having preserved 

 the details of image from fading. Robert Sabine. 



929. Specimens of Dujardin's photo-engraving process. 



Dujardin, Paris. 



930. Specimens of Photo-type Printing on Zinc. 



Capt. Abmy, R.E., F.R.S. 



931. Gillot's Photo-type Process. Veuve Gillot. 



932. First known Photograph on Glass, taken on pre- 

 cipitated silver chloride, by Sir J. Herschel (Slough, 1839.) 



Prof. A. S. Herschel. 



" Having precipitated muriate of silver in a very delicately divided state from 

 water very slightly muriated it was allowed to settle on a glass plate ; after 48 

 hours it had formed a film thin enough to bear drawing the water off very 

 slowly by a siphon, and drying. Having dried it I found that it was very 

 little affected by light, but with washing with weak nitrate of silver and drying 

 it became highly sensible. In this state I took a camera picture of the tele- 

 scope on it. Hyposulph. soda then poured cautiously down washes away the 

 muriate of silver, and leaves a beautiful delicate film of silver representing the 

 picture. If then the other side of the glass be smoked and black varnished 

 the effect is much resembling daguerreotype, being dark on white as in nature, 

 and also right and left as in nature, and as if on polished silver." Sir J. 

 Herschel (MS. Journal of Experiments). 



937b. Original Book of Experiments made by Sir J. 

 Herschel on the Metallic Salts sensitive to Light. 



Prof. A. S. Herschel. 



933. Second Daguerreotype Proof, obtained by Daguerre 

 in 1839. Conservatoire des Arts et Metiers, Paris. 



Lithographic Stone of Poiteven, with a proof on paper. 

 Conservatoire des Arts et Metiers, Paris. 



935. Photographs by Daguerre. M. Fizeau, Paris. 



937. Specimens illustrating the History of Photo- 

 graphy. French Photographic Society, Paris. 



937a. Daguerreotype full-length Portrait, taken in Paris 

 in 1840, by special appointment, on the roof of a house in the 

 open air, at 6 a.m. Exposure 20 minutes, in June sun. 



James Martin. 



938. Instantaneous Photograph. Waves breaking on the 

 shore of Britain in 1876. James Martin. 



939. Engravings with the Aid of Photography. 



MM. Goupil et Cie., Paris. 



