"Meditationis est perscrutari occulta; contemplationis est admirari perspicua . . . . . Admiratio generat quæstionem, quæstio investigationem, investigatio inventionem."-Hugo de S. Victore. ..... -"Cur spirent venti, cur terra dehiscat, J. B. Pinelli ad Mazonium. CONTENTS OF VOL. XLVII. (FOURTH SERIES.) NUMBER CCCIX.-JANUARY 1874. Mr. J. Y. Buchanan on an Apparatus for Gas-analysis. M. H. Herwig on the Disintegration of the Electrodes in the Prof. Challis's Theory of the Source of Terrestrial Magnetism. Page 1 6 14 22 25 M. A. F. Sundell on the Electromotive and Thermoelectric 28 49 Prof. W. F. Barrett on the Molecular Changes that accompany the Magnetization of Iron, Nickel, and Cobalt 51 Notices respecting New Books: 56 Mr. J. M. Wilson's Elementary Geometry Proceedings of the Royal Society : Dr. J. H. Gladstone and Mr. A. Tribe on an Air-Battery. 61 Proceedings of the Geological Society: Mr. S. Sharp on the Oolites of Northamptonshire.— On some Phenomena of Illumination, by A. Lallemand On a Process for verifying the Nodes in a Sounding Pipe, by NUMBER CCCX.—FEBRUARY. Lord Rayleigh on the Manufacture and Theory of Diffractiongratings.... Mr. O. Heaviside on Wheatstone's Bridge. Mr. J. Croll on the Physical Cause of Ocean-currents Prof. E. C. Pickering's Measurements of the Polarization of 67 74 77 80 81 93 94 122 127 Page Mr. R. Moon's Remarks on the Analytical Principles of Hydrodynamics, in Reply to Professor Challis 143 Dr. Helmholtz on Galvanic Polarization in Liquids free from 145 Notices respecting New Books: Mr. W. T. Pierce's Treatise on Practical Solid or Descrip- 153 Prof. M. Yarnall's Catalogue of Stars observed at the On a new Determination of the Mechanical Equivalent of Heat, by H. Serrano y Fatigati. 155 155 On the Expansibility of Ebonite by Heat, by F. Kohlrausch.. 156 On the Discharge of Electrified Conductors, by J. Moutier .. 157 NUMBER CCCXI.-MARCH. The Earl of Rosse on the Electric Resistance of Selenium .. 161 Mr. J. A. Phillips on the Composition of certain Mine Waters. 164 Mr. J. Croll on the Physical Cause of Ocean-currents. (With 168 a Plate.)..... M. H. Herwig on the Number and Weight of the Molecules 190 193 M. J. L. Soret on some Phenomena of Polarization by Diffusion of Light... 205 M. A. Terquem on the Transformation of the Vibroscope into 212 : The Rev. S. Hawtrey's Introduction to the Elements of 215 Proceedings of the Royal Society: Lieut. Sale on the Action of Light on the Electrical Re- 216 Mr. D. M'Kichan's Determination of the Number of 219 Mr. F. Chambers on the Diurnal Variations of the Wind 228 Proceedings of the Geological Society : Dr. J. Bryce on the Jurassic Rocks of Skye and Raasay. 229 Page Mr. T. Davidson on some Brachiopoda collected by Mr. 230 Prof. D. T. Ansted on Solfataras and deposits of Sulphur 230 Mr. J. Lucas on the Origin of Clay-Ironstone 231 231 Capt. F. W. Hutton on the younger formations of New 232 Mr. W. Carruthers on the Tree Ferns of the Coal-mea sures 233 Mr. A. H. Schindler on the Geology of Kazirùn 233 The Rev. T. G. Bonney on the Lakes of the North-eastern 234 Signor B. Gastaldi on the Effects of Glacier-erosion in 235 On the Limits of the effective Power of Microscopes, by Professor Helmholtz 236 Experimental Researches on Newton's Coloured Rings, by P. 236 On extraordinary developments of Light in the grinding of hard Stones, by Dr. Jacob Nöggerath 237 NUMBER CCCXII. APRIL. Prof. J. P. Cooke on the Vermiculites; their Crystallographic and Chemical Relations to the Micas; together with a discussion of the Cause of the Variation of the Optical Angle in these Minerals (With a Plate.) .... 241 277 M. H. Vogel on the Sensibility to Light of Bromide of Silver Sir B. C. Brodie on the Electric Decomposition of Car- 281 294 309 Messrs. Lockyer and Roberts on the Quantitative Ana- 311 |