CONTENTS OF VOL. XXXI. FOURTH SERIES. Vll 



Page 

 On a Gas-burner for Sounding large Tubes, by E. Reusch . . 401 

 Note on the Mechanical Equivalent of Light, by Moses G. Farmer 403 

 On the Composition of Forces, by Dr. Stevelly e 404 



NUMBER CCXL— JUNE. 



Mr. W. Huggins and Dr. W. A. Miller on the Spectra of some 



of the Fixed Stars. (With Two Plates.) 405 



Mr. I. Todhunter on a Problem in the Calculus of Variations. . 425 



Dr. A. Paalzow on the Heat of the Electric Spark 427 



Archdeacon Pratt on the Fluid Theory of the Earth 430 



Prof. Tyndall on Calorescence. (With a Plate) 435 



Dr. Atkinson's Chemical Notices from Foreign Journals .... 451 

 Prof. Challis on the Fundamental Ideas of Matter and Force 



in Theoretical Physics 459 



Proceedings of the Royal Society : — 



Mr. W. Huggins on the Spectra of some of the Nebulae, 

 with a mode of determining the Brightness of these 



Bodies 475 



Dr. Everett's Experiments on the Flexural and Torsional 

 Rigidity of a Glass Rod, leading to the determination of 



the Rigidity of Glass 476 



Proceedings of the Geological Society : — 



Messrs. St. Vincent Lloyd, Delenda, and Decigala on the 

 formation of a new island in the neighbourhood of the 



Kameni Islands 477 



Mr. J. B. Jukes on the Carboniferous Slate of North Devon 



and South Ireland 477 



Mr. W. B. Dawkins on the Fossil British Oxen 479 



Commander G. Tryon on the formation of a new island 



in the neighbourhood of the Kameni Islands 479 



Mr. T. M c Kenny Hughes on the Junction of the Thanet 



Sand and Chalk 479 



Mr. W. Whitaker on the Lower London Tertiaries of Kent 480 

 Mr. W. Keene on the Brown Cannel Coal-seams at Colley 



Creek . „ 481 



The Rev. W. B. Clarke on the Oil-bearing Deposits in New 



South Wales 481 



M. H. Bauerman on the Copper-mines of Michigan .... 482 

 On the Influence of the Electro-negative Elements upon the 



Spectra of the Metals, by M. Diacon 483 



On the Determination of the Refractive Equivalent of the Ele- 

 ments, by M. A. Schrauf 483 



NUMBER CCXII.— SUPPLEMENT. 



Drs. A. Fick and J.Wislicenus on the Origin of Muscular Power. 485. 



Mr. B. Stewart on the Solar Spectrum 503 



Prof. J. A. Wanklyn on the Action of Carbonic Oxide on 

 Sodium-ethyle 505 



