PROCEEDINGS OF 

 THE EOYAL SOCIETY. 



vol. xx. No. 137. 



i 



CONTENTS. 



]' If June 20, 1872 {continued). 



PAGE 



IV. Pyrology, or Fire Analysis. By Capt. W. A. Ross, R.A 449 



XV. On the Action of Electricity on Gases. By Sir B. C. Beodie, Bart., 

 F.R.S., Hon. D.C.L. Oxon., late Waynefiete Professor of Chemistry in 

 the University of Oxford 472 



XVI. Researches on the Atomic Weight of Thallium. By*WiLLiAH Ceookes, 



F.R.S. &c 475 



XVII. On the Spectrum of Nitrogen. By Aethue Schustee, Student at the 



Physical Laboratory of Owens College 484 



XVIII. On the Combined Action of Heat and Pressure upon the Paraffins. By 



T. E. Thoepe and J ohn Young, of the Andersonian University, Glasgow 488 



XIX. On the Echinidea of the ' Porcupine ' Deep-sea Dredging-Expeditions. 



By Prof. Wtville Thomson, LL.D., D.Sc, F.R.S 491 



XX. On Supersaturated Saline Solutions. By Archibald Liteesidge, Assoc. 

 R.S. Mines, and Scholar of Christ's College, Cambridge 497 



XXI. Note relating to the Attraction of Spheroids. By I. Todhuntee, M.A., 



F.R.S. 507 



XXII. Report on the Exploration of Brixham Cave, conducted by a Committee 

 of the Geological Society, and under the immediate superintendence and 

 record of Wm. Pengellt, Esq., F.R.S. , aided by a Local Committee ; 

 with Descriptions of the Organic Remains by G. Busk, Esq., 

 F.R.S., and of the Flint Implements by John Evans, Esq., F.R.S. By 

 J, Peestwich, F.R.S., F.G.S., &c, Reporter 51 i 



[For continuation of Contents see Mh page of Wrapper.~] 



