CONTENTS OF VOL. XLV, 



(FOURTH SERIES.) 



NUMBER CCXCVIL— JANUARY 1873. 



Dr. R. Konig on Manometric Flames. ("With a Plate.) ~1 



Prof. A. M. Mayer on an Acoustic Pyrometer. (With a Plate.) 18 

 Mr. H. A. Smith on the Chemistry of Sulphuric Acid-manu- 

 facture 23 



Mr. R. Moon on the Definition of Intensity in the Theories 



of Light and Sound 38 



Dr. A. Stoletow on the Magnetizing-Function of Soft Iron, 

 especially with weaker decomposnig-powers. (With a Plate.) 40 



M. E. Hagenbach's Experiments on Fluorescence 57 



Notices respecting New Books : — 



Prof. A. M. Mayer's The Earth a Great Magnet 65 



War Department Weather Maps. Signal-Service, United- 

 States Army 66 



Mr. J. N. Lockyer's The Atmosphere of the Sun 66 



Proceedings of the Royal Society : — 



Mr. A. Liversidge on Supersaturated Saline Solutions . . 67 



On the Distribution of Magnetism, by M. Jamin 76 



Relation between the Pressure and the Volume of Saturated 

 Aqueous Vapour which expands in producing Work with 

 neither addition nor subtraction of Heat, by H. Resal .... 77 

 On the Definition of Temperature in the Mechanical Theory 

 of Heat, and the Physical Interpretation of the Second Fun- 

 damental Principle of that Theory, by E. Mallard 77 



On Electro-magnetism, by M. Treve 80 



NUMBER CCXCVIIL— FEBRUARY. 



Dr. W. M. Watts on the Spectrum of the Bessemer-flame. 

 (With Two Plates.) 81 



Prof. A. M. Mayer on the Experimental Determination of the 

 Relative Intensities of Sounds ; and on the Measurement of 

 the Powers of various substances to Reflect and to Transmit 

 Sonorous Vibrations 90 



Mr. I. Todhunter on the History of certain Formulae in Sphe- 

 rical Trigonometry 98 



Mr. R. Moon on the Law of Gaseous Pressure 100 



