THE LONDON, EDINBURGH, AND DUBLIN PHILOSOPHICAL MAGAZINE AND JOURNAL OF SCIENCE. CONDUCTED BY SIR ROBERT KANE, LL.D. F.R.S. M.R.I.A. F.C.S. AND WILLIAM FRANCIS, PH.D. F.L.S. F.R.A.S. F.C.S. "Nec aranearum sane textus ideo melior quia ex se fila gignunt, nec noster vilior quia ex alienis libamus ut apes." JUST. LIPS. Polit. lib. i. cap. 1. Not. VOL. XL.-FOURTH SERIES. LONDON. TAYLOR AND FRANCIS, RED LION COURT, FLEET STREET, SOLD BY LONGMANS, GREEN, READER, AND DYER; SIMPKIN, MARSHALL AND Co.; SMITH AND SON, GLASGOW; HODGES AND SMITH, DUBLIN; AND PUTNAM, NEW YORK. 134.125 Sci 90.9 "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, Cur mare turgescat, pelago cur tantus ámaror, J. B. Pinelli ad Mazonium. 34-9 CONTENTS OF VOL. XL. Mr. J. Ball on the Cause of the Descent of Glaciers .. Archdeacon Pratt's Reply to M. Delaunay's objection to the late Mr. Hopkins's Method of determining the Thickness of the Earth's Crust by the Precession and Nutation of the Earth's Prof. E. Edlund on the Path of Electrical Induction- and Dis- junction-Currents through Gases of various Densities, and between Poles of different shapes Mr. A. S. Davis on a possible Cause of the Bright Line observed by M. Angström in the Spectrum of the Aurora Borealis .. Mr. R. Moon on the Solution of Linear Partial Differential Equations of the Second Order involving two Independent Mr. S. E. Phillips on a Simple Method of Constructing high Prof. von Bezold's Researches on the Electrical Discharge. The Rev. J. M. Heath on the Interchangeability of Heat and Proceedings of the Royal Society :- Mr. Warren De La Rue, Dr. Balfour Stewart, and Mr. B. Loewy on the Positions and Areas of the Spots observed at Kew during the years 1864-66, also the Spotted Area Mr. H. E. Roscoe and Dr. T. E. Thorpe on the Relation between the Sun's Altitude and the Chemical Intensity of Total Daylight in a Cloudless Sky Prof. C. Piazzi Smyth on Supra-annual Cycles of Tempe- rature in the Earth's Surface-crust The Rev. S. Haughton on the Constituent Minerals of the Granites of Scotland, as compared with those of Donegal. Proceedings of the Geological Society :- Prof Huxley on Hypsilophodon, a new Genus of Dinosauria |