PROCEEDINGS OF 

 THE ROYAL SOCIETY. 



vol. xvii. No. 113. 



CONTENTS. 



^ T ->;V . 17,1869. 



PAGE 



I. Note on Professor Sylvester's representation of the Motion of a free rigid 

 Body by that of a material Ellipsoid rolling on a rough Plane. By the 

 Rev. N. M. Ferrers, Fellow and Tutor of Caius College, Cambridge . 471 



II. On the Origin of a Cyclone. By Henry F. Blaneord, F.G-.S., Meteoro- 

 logical Reporter to the Government of Bengal 472 



TIT. Note upon a Self-registering Thermometer adapted to Deep-sea Soundings. 



By W. A. Miller, M.D., Treas. and V.P.R.S 482 



1 V. Magnetic Survey of the West of France. By the Rev. Stephen J. Perry, 



F.R.A.S., F.M.S 486 



V. An Account of Experiments made at the Kew Observatory for deter- 

 mining the true Yafcuum- and Temperature- Corrections to Pendulum 

 Observations. By Balfottr Stewart, F.R.S.. and Benjamin Loewy, 

 F.R.A.S 488 



VI. Additional Observations on Hydrogenium. By Thomas Graham, F.R.S., 



Master of the Mint 500 



VII. Spectroscopic Observations of the Sun (continued). By Lieut. J. Her- 



schel, in a Letter addressed to W. Huggins, F.R.S 506 



VIII. On Jargonium, a new Elementary Substance associated with Zirconium. 



By H. C. Sorby, F.R.S. &c 511 



IX. Solar Radiation. By J. Park Harrison, M.A 515 



Index 



. . . . . . . .519 



[See last page of Wrapper. 



