VI CONTENTS OK VOL. XVII. — I'OUilTH SEllIKS. 



Page 



Mr. J. Ball on the Veined Structure of Glaciers 263 



The Rev. T. R. Robinson on the Stratification of Electric Light. 269 



Dr. Atkinson's Chemical Notices from Foreign Journals 275 



Messrs. W. H. Perkin and B. F. Duppa on the Action of Pen- 



tachloride of Phosphorus on Malic Acid 280 



Prof. Challis on a Method of finding the impossible Roots of 



an Equation, in rejjly to the Astronomer Royal 283 



Prof. Chidlis on the Theory of EUiptically-polarized Light. . . . 285 

 Proceedings of the Royal Society : — 



Dr. Frankland on Sodium-ethyle and Potassium-ethyle . . 289 

 Messrs. J. B. Lawes and Dr. Gilbert on the Composition 



of Animals fed and slaughtered as Human Food 291 



Mr. B. C. Brodie on the Formation of the Peroxides of the 



Radicals of the Organic Acids 301 



Dr. Hofmann on the Sulphocyanide and Cyanate of 



Naphtyle 304 



Proceedings of the Geological Society : — 



Mr. E. W. Binney on the occurrence of Liassic Deposits 



near Carlisle 305 



Mr. J. W. Salter on the Fossils of the Lingula-flags .... 306 



Prof. Huxley on a new species of Dicynodon 306 



Mr. R. Thornton on the Coal found by Dr. Livingstone at 



Tete, South Africa 307 



The Hon. C. A. Murray on some Minerals from Persia. . 307 

 Mr. J. W. Tayler on the Veins of Tin-ore at Evigtok, 



Greenland 307 



Mr. J. W. Kirkby on the Permian Chitonidae 308 



Mr. J. W. Dawson on the Vegetable Structures in Coal. . 308 



On Steam-ship Propulsion 310 



Note on the Polarization of the Light of Comets, by Sir David 



Brewster 311 



New Apparatus for observing Atmospheric Electricity, by Prof. 

 W. Thomson 312 



NUMBER CXV.-MAY. 



Mr. W. S. Jevons on the Semidiurnal Oscillation of the Baro- 

 meter 313 



Sir D. Brewster on the Coloured Houppes or Sectors of Hai- 

 dingcr 323 



Archdeacon Pratt on the Thickness of the Crust of the Earth. . 327 



Prof. Callan on an Induction Coil of great power in proportion 

 to its length 332 



Mr. J. N. Hearder on a New Form of Telegraph Cable intended 

 to reduce the effects of Inductive Action 334 



Mr. J. J. Waterstun on the relation of Common and Voltaic 

 Electricitv 345 



