148 Dr Fyfe on Photography. 



as when it has to permeate merely a frame of glass. The 

 same is the case when the light is reflected, and hence the ne- 

 cessity of getting quit of the mirror placed in cameras, for 

 throwing the representation in such a way as to allow of it 

 being traced by the artist. Hence, in taking impressions by 

 the camera, the prepared paper must be fixed on the back of 

 the box, directly opposed to the lens, and the focus properly 

 adjusted. I have found great advantage, in taking impressions 

 by the camera, in using the paper moist, and keeping it so 

 all the time it is exposed. For this purpose, after moisten- 

 ing it, I place it between a cushion and a pane of glass, tied 

 tightly together, to prevent, as much as possible, the escape 

 of moisture. In this way I have succeeded in a few minutes 

 in getting a faint outline of the object exposed to the lens. 



I may here mention that the camera affords a good method 

 of taking profiles from busts, not by the reflected light from 

 the bust, but by interposing it between the lens and the source 

 of light. The bust, for instance, may be placed, during sun- 

 shine, at an open window, and the image from it thrown on 

 the prepai'ed paper ; using the precaution, of having the face 

 slightly inclined towards the som'ce of light, so as to give its 

 outline as distinctly as possible. 



Etchings. — A method of taking impressions of etchings on 

 glass by the photographic process was described by Havell 

 of London. For this purpose the glass is covered with 

 etching varnish, and after the figure is etched on it, it is 

 smoked, so as to darken the varnish to prevent the transmis- 

 sion of light ; of course, the smoke does not adhere to those 

 parts of the glass exposed by the etching needle, and is there- 

 fore easily wiped off with a cloth, thus leaving the etcliing 

 free for the light to pass through. On exposing this with the 

 prepared paper behind it, a beautiful impression is taken. In 

 taking impressions in this way, the varnished side must be 

 placed next the paper, which must be kept close upon the 

 etching by means of a cushion, otherwise the impression is 

 not well defined. When the glass side is next the paper, the 

 impression is very indistinct, owing to the light, when it passes 

 through the exposed parts of the glass, being diffused, and 1)y 

 which the lines run into each other. 



