[ ] 
XV. All Instrument of Precision for Producing Monochromatic Light of any desired^ 
Wave-length, and its use in the Investigation of the Optical Properties of 
Orystals. By A. E. Tutton, Assoc. P.C.S., Demonstrator of Chemistry at 
the Royal College of Science, South Kensington, Communicated hy Professor 
Thorpe, F.R.S . page 913 
XVI. On the Specific Heats of Gases at Constant Volume .—Part TI. Carhon Dioxide. 
By J. JoLY, M.A., Sc.D., F.R.S. .' . 943 
XVII. On the Specific Heats of Gases at Constant Volume .—Part III, The Specific 
Heat of Carhon Dioxide as a Function of Temperature. By J. Joly, M.A., 
Sc.D., F.R.S. .'. 961 
XVIII. On the Photograp)hic Arc Sp>ectruni of Electrolytic Iron. By J. Norhax 
Lockyer, C.B., F.R.S. . 983 
XIX. On the Photographic Arc Spectrum of Iron Meteorites. By J. Normay 
Lockyer, C.B., F.R.S. . 1023 
XX. Flame Spectra at High Temperatures .—Part II. The Spectrum of Metallic 
Manganese, of Alloys of Manganese, and of Comp)Ounds containing that 
Element. By W, N. Hartley, F.R.S., Professor of Chemistry, Royal College 
of Science, Dublin . 1029 
XXL Flame Spectra at High Temperatures .—Part III. The Spectroscopic Phenomena 
and Thermo-Chemistry of the Bessemer Process. By W. N. Hartley^ F.R.S., 
Professor of Chemistry, Royal College of Science, Dublin . 1041 
Index to Part II.. 
1093 
