CONTENTS OF VOL. XLIX. 



(FOURTH SERIES.) 



NUMBER CCCXXIL— JANUARY 1875. 



Page 



Mr. F. Guthrie on Salt Solutions and Attached "Water 1 



Dr. E. J. Mills on Aniline Derivatives 21 



Mr. P. Smyth on Carbon and Hydrocarbon in the Modern Spec- 

 troscope. (With Two Plates.) 24 



Mr. F. Galton on Statistics by Intercoruparison, with Remarks 



on the Law of Frequency of Error 33 



Prof. A. M. Mayer on a new Method of investigating the 



Composite Nature of the Electric Discharge 47 



M. J.-L. Soret on Polarization by Diffusion of Light 50 



Prof. A. S. Herschel on the Spectrum of the Aurora 65 



Notices respecting New Books : — 



Dr. W". Spottiswoode on the Polarization of Light .... 72 

 Proceedings of the Geological Society : — 



Prof. A. C. Ramsay on the Physical History of the Valley 



of the Rhine 73 



Mr. "W. Topley on Upheaval and the Thickening of 



Subjacent Beds 73 



Mr. G. Maw's Geological Notes on a Journey from Algiers 



to the Sahara 75 



Mr. T. Davidson and Prof. W. King on the Trimerellid*. 76 

 On the Permanent Ice in a Mine in the Rocky Mountains, by 



R. Weiser 77 



On the Mixture of Colours in Binocular Vision, by "W. von 



Bezold 78 



Experimental Studies on the Electrical Resistance of Metals 

 and its Variation under the Influence of Temperature, by 



M. Rene Benoit 78 



On the Conservation and the Properties of a Plate of Palladium 

 saturated with Hydrogen by Electrolysis, by R. Bottger . . 80 



NUMBER CCCXXHL— FEBRUARY. 



Prof. E. Bouty's Studies on Magnetism 81 



Mr. R. H. M.Bosanquet on the Mathematical Theory of Mr. 



Baillie Hamilton's String-Organ 1 98 



Dr. "W. Marshall Watts on Carbon and Hydrocarbon in the 



Modern Spectroscope 104 



