CONTENTS OF VOL. XXI. FIFTH SERIES. Vll 



NUMBER CXXXIIL— JUNE. 



Dr. Werner Siemens on the Conservation of Energy in the 



Earth's Atmosphere 453 



Lord B,ayleigh's Notes, chiefly Historical, on some Funda- 

 mental Propositions in Optics 466 



Prof. S. P. Thompson on some New Polarizing Prisms. 



(Plate VI.) 476 



Mr. S. H. Burbury on the Foundations of. the Kinetic Theory 



of G-ases. Note on Professor Tait's paper 481 



Mr. C. Tomlinson on a new Theory of Dew 483 



Mr. H. Wilde on the Efflux of Air as modified by the Form 



of the Discharging Orifice 494 



Mr. F. T. Edgeworth on the Determination of the Modulus 



of Errors 500 



Notices respecting Isew Books : — 



Mr. W. Crookes's Select Methods in Chemical Analysis 



(chiefly Inorganic) 507 



Fourth Annual Eeport of the United States Geological 



Survey, for 1882-83 510 



" Photo-relief" Maps 511 



Proceedings of the Geological Society : — 



Mr. G-. W. Lamplugh on Glacial Shell-beds in British 



Columbia 512 



Mr. A. B. Wynne on a certain Fossiliferous Pebble-band 



in the " Olive group" of the Eastern Salt-range, Punjab 513 

 M. F. L. Cornet on the Phosphatic Beds in the neigh- 

 bourhood of Mods 513 



On Magnetization, by M. Mascart 515 



On an Instrument for Reproducing an Invariable Quantity 



of Electricity, by M. Marcel Deprez 518 



Experiments in Thermoelectricity, by MM. Pilleur and E. 



Jannetaz 519 



On the Origin and the Laws of Atmospheric Electricity, by 

 Prof. Franz Exner 520 



Index 521 



