vi CONTENTS OF VOL. XIII. — FOURTH SERIES. 



Page 



Prof. Tj-ndall on Foam and Hail 352 



Wr. J. Cockle on the Theory of Equations of the Fifth Degree. 354 

 Mr. D. Forbes on the Chemical Composition of the Silurian 



and Cambrian Limestones 365 



Proceedings of the Royal Society 373 



Geological Society 385 



Experiments on the Artificial Formation of the Hydrated Car- 

 bonates of the Earths and Metals, by A. Damour 388 



Note on a new C}^anometer, by Felix Bernard 389 



Comparative Examination and Analysis of Eudialite and Euko- 



lite, by A. Damour 391 



NUMBER LXXXVIII.— JUNE. 



M. G. Kirchhoff on the Motion of Electricity in Wires 393 



Mr. J. P. Nichol on Parallel Lines 412 



Mr. A. H. Church on Parabenzole, a new Hydrocarbon from 



Coal-naphtha 415 



Mr. A. Cay ley on the Summation of a certain Factorial Ex- 

 pression 419 



Mr. A. Cayley on a Theorem relating to the Rectangular Hy- 

 perbola ' 423 



Prof. Odling on the Natural Groupings of the Elements. — Part I. 423 

 Prof. Schonbein on the Connexion of Catalytic Phsenomena 



with AUotropy (concluded) 440 



Proceedings of the Royal Society 452 



Geological Society 462 



On the Temperature of Foam, by Henry M. Witt 467 



Description of a new Barometer, by M. Davoust 468 



On a new locality for the mineral Atacamite, by J. J. Monteiro. 470 

 Note on the Improved Induction Coil, by C. A. Bentley .... 471 

 On the Absorption of Light in traversing Comets, byM. Babinet. 471 



NUMBER LXXXIX.— SUPPLEMENT TO VOL. XIII. 



Prof. Tyndall on the Sounds produced by the Combustion of 



Gases in Tubes 473 



Prof. Odling on the Natural Groupings of the Elements 480 



Dr. Atkinson's Chemical Notices from Foreign Journals .... 497 

 M. F. on the Persistent Appearance of the Lightning Flash . . 506 

 Mr. A. Cay ley's Analytical Solution of the Problem of Tactions. 507 

 Prof. Haughton's Notes on Mineralogy. — No. V. On Hypo- 



stilbite and Stilbite 509 



Proceedings of the Royal Society 511 



— Geological Society 529 



