Drawing to be exhibited with Abney's colour photometer. Size 20"x11" Drawing to be exhibited with Abney's colour photometer. Size 20"x11"
Adjustable skeleton telescope: consisting of optical bench and two sliding mounts with two 38mm diam. lenses - 1 convex 12 dioptres, 1 convex 2 dioptres. Constructed Nov.1932 for special optical exhibition Adjustable skeleton telescope
Double-sided brooch, two tinted ambrotypes; brass mount, scroll decoration, convex celluloid ropework decoration, 27 mm. Double-sided brooch
Diagram illustrating the principle of the parallax stereogram, in glased mahogany frame Diagram illustrating the principle of the parallax stereogram