Price HALF-A-CROWN. 7 



Subscription Price, TWENTY-FIVE SHILLINGS per Annum, Post Free. 



VOL. V. 



No. 30. 



ctence 



A MONTHLY REVIEW OF CURRENT SCIENTIFIC INVESTIGATION. 



Conducted by HENRY C. BURDETT. 



Edited by J. BRETLAND FARMER, M.A. 



WITH THE COOPERATION OF THE FOLLOWING EDITORIAL COMMITTEE:— 



Professor of Chemistry at the City and Guilds of London Institute for Technical 



Professor of Chemistry, St. Thomas' Hospital and Pharmaceutical Society, 



H. E. ARMSTRONG, F.R.S 

 Education. 



W. R. DUNSTAN, F.R.S. 

 London. 



G. F. FITZGERALD, F.R.S., Professor of Natural and Experimental Philosophy in the University of Dublin. 



C. S. SHERRINGTON, F.R.S., Professor of Physiology in University College, Liverpool. 



J. W. JUDD, C.B., F.R.S., Dean of the Royal College of Science, London. 



W. J. SOLLAS, F.R.S., Professor of Geology in the University of Dublin. 



G. B. HOWES, F.Z.S., Professor of Zoology, Royal College of Science, London. 



H. MARSHALL WARD, F.R.S., Professor of Botany in the University of Cambridge. 



H. A. M1ERS, F.R.S., Professor of Mineralogy in the University of Oxford. 



AUGUST, 1896. 



CONTENTS. 

 By OLIVER LODGE, F.R.S., Professor of Physics 



By A. C. SEWARD, M.A., F.G.S., 



By PHILIP LAKE, 



LIGHT AND ELECTRIFICATION, II 



in University College, Liverpool 



AN EXTINCT PLANT OF DOUBTFUL AFFINITY 



University Lecturer in Botany, Cambridge ... 



THE WORK OF THE PORTUGUESE GEOLOGICAL SURVEY. 



M.A., St John's College, Cambridge ... 



IODINE IN THE ANIMAL ORGANISM. By W. D. HALLIBURTON, M.D., F.R.S., Pro- 

 fessor of Physiology in King's College, London 



PETROLOGY IN AMERICA. By ALFRED HARKER, M.A., Fellow of St. John's College, 

 Cambridge 



GOLD EXTRACTION PROCESSES. By T. K. ROSE, D.Sc, Assistant Assayer of the 

 Royal Mint 



RECENT VALUES OF THE MAGNETIC ELEMENTS AT THE PRINCIPAL MAG 

 NETIC OBSERVATORIES OF THE WORLD. By Charles Chree, M.A., Superin- 

 tendent of the Kew Observatory 



APPENDIX: 



CHEMICAL LITERATURE FOR JUNE, 1896 



PAGE 



417 



427 



439 



454 



459 



484 



499 



XLVII 



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