APPENDIX I. 251 



(b) Whether coloured fibres owe their tint to natural pigment 

 or dye. The pigment cells appear as separate units, 

 while the dyed fibres appear of uniform tint through- 

 out. 

 Messrs. Jeyes' Sanitary Compounds Company, Ltd. (Mr. 

 W. C. Reynolds, F.I.C). — Illustrating the theory of emulsions. 



Messrs. Kodak, Ltd. — Filters for photomicrography, spectro- 

 scopy, tri-colour photography, filter-holders and other photomicro- 

 graphical accessories, plates for photomicrography. 

 The Photomicrographic Society. — 



Mr. F. Martin Duncan, F.R.M.S., F.R.P.S., F.Z.S.— 

 Prints of low and high power photomicrographs, includ- 

 ing bacteria, etc. 

 Dr. G. H. Rodman, F.R.P.S. — Transparencies of photomicro- 

 graphs of a variety of subjects, in viewing frame. 

 Mr. E. a. Pinchin, F.R.M.S. — Transparencies of photo- 

 micrographs of diatoms, in viewing frame. 

 Mr. F. Ian G. Rawlins. — A moderate-sized " ordinary " micro- 

 scope, modified for use in metallography. 

 Features : — 



(a) Substage arrangement. 



(b) Modified objectives (converted to short barrel from 

 standard lenses). 



(c) Half -watt lamp, affording sufficient illumination at 

 minimum expense and trouble. 



Mr. J. Rheinberg. — Some Applications of: — 



(1) Filmless photography. 



(2) Grainless photography. 



(3) Platinised and semi-platinised surface mirrors. 



Mr. Sydney W. Ross, F.R.M.S. — A new apparatus for the 

 microscopic examination and photomicrography of metallic specimens 

 {two forms, drawings only). 



Research Department, Woolwich. • 



(1) Microscope with filar micrometer eye-piece, used for the 



measurement of small Brinell ball hardness impressions 

 (0.2 to 0.8 millimetre in diameter) to 0.001 millimetre. 



(2) Photomicrographs of structures found in gun-steel, shell- 



steel, etc. 

 M. Eugene Schneider and M. Charles Florian. — A micro- 

 scope for measuring Brinell depressions. (Constructed by the Societe 

 <l'Optique et de Mecanique de Haute Precision, Paris.) 



Sheffield University, by kind permission of the Yice-Chan- 

 •cellor, Sir W. H. Hadow (Professor W. Ripper, and Dr. J. O. 

 Arnold, F.R.S.). 



Original Spcriwens Belonginrf to Soil]/. 

 (1) The following is a description of the Sorby micro-sec- 

 tions : — 



Dr. PI. C. Sorby's pioneer micro-sections of iron and 

 steel, made in 1863-5. 



Lent in 1889, for Dr. Sorby's lifetime, to Professor 

 J. O. Arnold, F.R.S., and bequeathed on Dr. Sorby's 



