61 
BOTANICAL SECTION. 
Botanical Walk, Tuesday, Sept. 4th. — No report received up 
to the time of going to press. 
CHEMICAL AND PHOTOGRAPHIC SECTION. 
Wednesday, September 12th. — Mr. P. J. Worsley, F.C.S., 
President, in the chair. 
Mr. J. Beattie gave a verbal description of Pouncey's Carbon- Print- 
ing process. He stated that Pouncey had worked very laboriously to find 
a process of printing permanent sun-pictures, with all the qualities of 
prints taken by silver salts. His first plan was with chromate of potash 
and gelatine, which by exposure to light was hardened and rendered 
insoluble in water. The results of this process were very crude. He next 
tried Swan's process, with gelatine and Bichromate of Ammonia; and 
finally he devised a plan of printing in lithographic ink. He proceeded as 
follows : — Take a sheet of bag paper, make transparent with nut oil, and 
coat with a thin dim of gelatine. Then take any oily pigment, as litho- 
graphic ink, and grind up with bitumen and benzole, and brush over the 
paper with it. Dry in the dark. Expose it to the negative from the back. 
Then dissolve out with turpentine, of which several baths are used. The 
picture is then dried and coated with a transparent varnish, which is 
allowed to dry till it becomes ' tacky.' It is then laid on card, or paper, or 
other material (to which it is desired to transfer it) and pressed. The 
thin paper is then stripped off, and the perfect picture left. Mr. Beattie 
exhibited some fine specimens on paper, wood, and canvas, and they quite 
bore out the high eulogium he pronounced on the process. If suitable 
colouring materials are used, the pictures can be transferred to porcelain, 
and burnt into the glaze. 
Mr. Worsley exhibited some specimens of Swan's process, which 
had been furnished by that gentleman. 
Mr. Beattie considered that the fine surface obtained by Mr. Swan 
rendered his process most suitable for portraits, while Pouncey's was 
by far the best for landscapes. 
