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Ordinary Meeting, April Ist, 1884. 



H. E. ROSCOE, Ph.D., LL.D., F.RS., &c., President, 

 in the Chair. 



Mr. Brothers, F.RA.S., described the Woodburytype 

 and Stannotype processes. He said that Mr. Woodbury's 

 first idea was to produce pliotographs in gelatine relief to 

 imitate porcelain relief pictures, but he found that by using 

 a low relief the image could be pressed into soft metal, and 

 from the impressed image prints on paper could be obtained 

 in gelatine combined with pigment of any colour. Pictures 

 of this kind could be made so closely imitating ordinary 

 silver prints that it was difficult to detect the difference. 

 Owing to the difficulty of obtaining plates witli perfectly 

 flat surfaces and the great pressure required to produce the 

 impression in metal, the size of the Woodburytype picture 

 was limited. It occurred to Mr. Woodbury that a gelatine 

 negative having sufficient relief could itself be printed from, 

 but as the use of fluid gelatine for the prints would soften 

 the negative, it was necessary to protect the surface, and 

 for this purpose he covers the negative with thin sheets of 

 tinfoil, which is passed between indiarubber rollers, which 

 cause the thin metal to take the impression of the negative 

 completely, and the glass plate (which is of the ordinary 

 thickness) bearing the negative covered with tinfoil could 

 now be used as the ordinary Woodburytype plate, and 

 printed from in the same way. Mr. Brothers showed 

 some of the original Woodburytype prints, and from a metal 

 plate showed the method of printing — the plate being a 

 portrait of Mr. Woodbury. A Stannotype plate was also 

 shown and prints side by side, with silver prints from the 

 same negative. 

 Proceedings— Lit. & Phil. Soc— Vol. XXIII.— No. 8.— Session 1883-4. 



