CONTENTS of N° 280.— Fourth Series. 



XXIX. On Ocean-currents. — Part III. On the Physical Cause of 

 Ocean-currents. By James Croll, of the Geological Survey of 

 Scotland page 24 



XXX. The Solid Crust of the Earth cannot be thin. By Arch- 

 deacon Pratt, M.A., F.R.S 28( 



XXXI. On the Action of Light on Chlorine and Bromine, By Dr. 



E. Budde, of the University of Bonn 29 



XXXII. On a Class of Definite Integrals. By J. W. L. Glaisher, 

 B.A., F.R.A.S., F.C.P.S 29 



XXXIII. On a new Method of solving some Problems in the Cal- 

 culus of Variations, in reply to Professor Cayley. By the Rev. Pro- 

 fessor Challis, M.A., F.R.S 30 



XXXIV. Contributions to the History of the Phosphorus Chlo- 

 rides. By T. E. Thorpe, Ph.D., F.R.S.E ; 



XXXV. On the Existence of Sulphur Dichloride. By John Dal- 

 zell and T. E. Thorpe, Ph.D., F.R.S.E , 30 



XXXVI. On Gauss's Pentagramma mirificum. By Professor 

 Cayley, F.R.S 31 



XXXVII. Notices respecting New Books : — Elements of Plane and 

 Solid Geometry. By H. W. Watson, M.A., some time Fellow of 

 Trinity College, Cambridge. — Select Methods in Chemical Analysis 

 (chiefly Inorganic). By William Crookes, F.R.S. &c 312-31 



XXXVIII. Proceedings of Learned Societies :— 

 Geological Society : — Sir Philip Grey Egerton on a New 



Chimseroid Fish from the Lias of Lyme Regis ; Mr. A. Geikie 

 on the Tertiary Volcanic Rocks of the British Islands ; The 

 Rev. T. G. Bonney on the formation of ' Cirques ' . . . . 315-31 



XXXIX. Intelligence and Miscellaneous Articles : — 



On the Spectra of Sulphur, by M. G. Salet 31 



On some Luminous Tubes with Exterior Electrodes, by M. Al- 

 vergniat * 31 



On the Amount of Time necessary for Vision, by Ogden N. Rood, 

 Professor of Physics in Columbia College t 32 



It is requested that all Communications for this Work may be addressee 

 post-paid, to the Care of Messrs. Taylor and Francis, Printing Office, Re| 

 Lion Court, Fleet Street, London. 



