﻿IV CONTENTS OF VOL. XLI. — FOURTH SERIES. 



Page 

 Mr. C. E. De Ranee on the Preglacial Deposits of Western 



Lancashire and Cheshire 78 



The Rev.W. Bleasdell on Modern Glacial Action in Canada, 78 

 On the Spectrum of the Aurora Borealis, by John Browning, Esq. 79 

 Note on the use of Eye-screens in Telescopic and other Re- 

 searches, by Richard A. Proctor, B.A 79 



NUMBER CCLXXI.— FEBRUARY. 



Mr. J. Ball on the Cause of the Motion of Glaciers 81 



Mr. J. A. Phillips on the Chemical Composition and Microscopic 



Constitution of certain Cornish Rocks 87 



The Hon. J. W. Strutt on the Light from the Sky, its Polariza- 

 tion and Colour 107 



The Rev. T. K. Abbott's Addendum to a Paper on the Theory 



of the Tides 120 



M. F. Zollner on the Spectrum of the Aurora borealis 122 



The Rev. J. M. Heath on Athermogenic Condensation 127 



M. S. Merz on a small Universal Stellar Spectroscope. (With a 



Plate.) 129 



Mr. T. T. P. B.Warren on the Estimation of Zinc on Galvanized 



Iron 132 



M. C. Marignac's Researches on the Specific Heats, Densities, 



and Expansions of some Liquids 134 



Proceedings of the Geological Society : — 



The Rev. J. M. Mello on an altered Clay-bed and Sections 



in Tideswell Dale, Derbyshire 154 



Dr. R. Brown on the Physics of Arctic Ice as explanatory 



of the Glacial Remains in Scotland 154 



Proceedings of the Royal Geological Society of Ireland : — 



Mr. E. Hull on the Geological Age of the Ballycastle 

 Coal-field, and its relation to the Carboniferous Rocks 



of the West of Scotland 155 



On some Hydro- and Thermoelectric Forces, reduced to Sie- 

 mens's Unit of Resistance and Weber's Unit of Current, by 



F. Kohlrausch 157 



On the Duration of Flashes of Lightning, by O. N. Rood .... 159 



NUMBER CCLXXIL— MARCH. 



Prof. R. Bunsen's Calorimetric Researches. (With a Plate.) . . 161 

 Mr. W. R. Birt on some recent Investigations relative to Lunar 



Activity. (With Two Plates.) 183 



M. F. Zollner on the Influence of Density and Temperature on 



the Spectra of Incandescent Gases 190 



