CONTENTS of N° 259.— Fourth Series. 



XII. On Ocean-currents. — Part I. Ocean-currents in relation to 

 the Distribution of Heat over the Globe. By James Croll, of the 

 Geological Survey of Scotland page 81 



XIII. Note on an Elementary Proof of a Theorem of Lagrange's. 



By Professor Robert Stawell Ball, A.M 107 



XIV. On the determination of the size of the Wire which, wound 

 upon a Galvanometer or Electromagnet, will produce the maximum 

 magnetic effect in a Circuit of given external resistance. By G. K. 

 Winter, Telegraph Engineer, Madras Railway Company. (With a 

 Plate.) 109 



XV. Determination of the Absolute Horizontal Intensity of the 

 Earth's Magnetism by Measurement of a Current. By F. Kohlrausch. 114 



XVI. Remarks on the Atomic Theory. By W. H.Walenn, F.C.S. 122 



XVII. Fundamental Principles of Molecular Physics. By Professor 



W. A. Norton 126 



XVIII. Memoir on the Expansion of Gases. By M. V. Regnault. 127 



XIX. Proceedings of Learned Societies : — 



Royal Society : — Dr. H. E. Roscoe's Researches on Vana- 

 dium ; Dr. T. Andrews on the Continuity of the Gaseous and 

 Liquid States of Matter 146-153 



XX. Intelligence and Miscellaneous Articles : — 



On the Simultaneous Occurrence of a Soluble Lead-salt and free 

 Sulphuric Acid in Sherry Wine; with observations on the 

 Solvent Action of Alcoholic Saline Solutions upon Sulphate 

 of Lead, by Professor F. H. Storer 154 



On Auroral Appearances and their connexion with the Pheno- 

 mena of Terrestrial Magnetism, by Balfour Stewart, F.R.S., 

 F.R.A.S 159 



It is requested that all Communications for this Work may be addressed, 

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

 Lion Court. Fleet Street, London. 



