244 Proceedings of the Asiatic Society. [ Noy. 
washed in several changes of water till all the bichromate is re- 
moved and is ready for printing. 
The printing is the most difficult part of the whole process and suc- 
cess appears to depend entirely upon the composition of the ink, In 
printing line subjects some inks are too tough and cannot well be 
cleaned off the plate, others are too soft and are liable to be rubbed off 
when the plate is cleaned with a cloth. Then again in printing sub- 
jects in half tone a stiff ink will only take on the shadows, while a soft 
thin ink will take all over the plate and by giving a slight tone to 
the high lights destroy all brilliancy of effect. In printing subjects 
in line I rollin with a tolerably stiff ink made of ordinary lithogra- 
phic chalk ink thinned with olive oil instead of varnish and before 
printing, clean the surface of the plate with a damp cloth. For 
half tone subjects, the plate must first be rolled in with stiff ink in 
order to obtain depth in the shadows and the detail of the half 
tones afterwards brought out by the use of a softer and lighter 
ink which should just be of such a consistency and tint that the 
half tones may all be well developed, but the high lights left clear. 
The inking in may be done with lithographic rollers, but rollers of 
india-rubber have been found better. The printing is best per- 
formed by vertical pressure in an ordinary type printing press 
which should be furnished with an india-rubber bed to prevent 
the glass plates being broken, and the plate should be covered with 
a padding of felt, so that the paper may be well pressed into the 
hollows forming the deepest shadows. Enamelled paper is the 
best for printing on, especially for subjects in half tone. The proofs 
I have with me have all been pulled in an ordinary copying press 
which I find answers the purpose fairly, though it is inconvenient 
in many respects. 
If it is required to print on a tissue, a plan which certainly possess- 
es many great advantages, a perfectly polished glass plate is used 
instead of ground glass, and the surface is rubbed with a solution 
of wax in ether, so that when it is dry, the film may be stripped off 
with ease. The composition I have described abéve makes an ex- 
cellent tissue. 
Such are the details of my process as far as I have gone, 
‘it is very imperfect in many points, but I am_ still working 
