376 Graphotype. | 
heating, and disappears perfectly by cooling. To prepare 
it, take one part bromide of potassium, one part blue vitriol, 
eight parts of water. It is better also to discolour the blue 
vitriol with one part of alcohol. 
Amusing Application—A winter scene may be so exe- 
cuted that the green leaves of the trees and the grass on 
the foreground are painted with ink made from cobalt and 
nickel solution, No. 5; the red berries and flowers with 
No. 1; yellow flowers and fruits with No. 2; and the blue 
flowers with pure cobalt, No. 5. When such a picture is 
slowly and carefully heated, the invisible parts of the plants 
become visible, and it is as if the heat changed the winter 
into asummer scene. There are several other substances 
which may be used for invisible writing, which becomes so 
by heating—lemon and onion juice, milk, diluted sulphuric 
acid, Gzc:, Sc. 
GRAPHOTYPE. 
OME months ago, we noticed this process for doing 
away with the labour of the engraver in our pages, 
since which time it appears to have made great strides, not 
only with publishers, in spite of the interested opposition 
it naturally meets with, but in the estimation of the public, 
who view the process as a great gain to art. 
It is now being used for preparing blocks for colour 
printing ; and H.R.H. the Prince of Wales, who visited 
the company’s premises the other day, accompanied by the 
Duke of Edinburgh, Lord Newry, &c., has entrusted them 
with a valuable drawing, representing the Prince and Suite 
shooting wolves, &c., made by order of the Emperor of 
Russia, and presented to the Prince as a memento of his 
visit to that country, to be executed in fac simile by the 
process. 
The invention is also being turned to account in the 
working of patterns in inlaid metals, to which the name of 
Intagliography has been given, and very great results may 
be anticipated in that direction. In fact, the applications 
likely to be made of the art are so varied and numerous, 
that it is impossible to foresee the extent of its future; 
but we may call the attention of our readers to the 
