CONTENTS — {continued) . 



PAGE 



VI. On the Measurement of the Chemical Intensity of Total Daylight made at 

 Catania during the Total Eclipse of Dec. 22, 1870. By Heney E. Eoscoe, 



E. E.S., and T. E. Thoepe, E.E.S.E 511 



VII. On the Calculation of Euler's Constant. By J. W. L. Glaishee, B.A., 



F. R.A.S 514 



VIII. Records of the Magnetic Observations at the Kew Observatory. No. IV. — 

 Analysis of the principal Disturbances shown by the Horizontal and Ver- 

 tical Force Magnetometers of the Kew Observatory from 1859 to 1864. 

 By General Sir Edwaed Sabine, K.C.B., President 524 



IX. Amended Rule for working out Sumner's Method of finding a Ship's 



Place. By Professor Sir William Thomson, F.R.S 524 



X. On Linear Differential Equations.— No. V. By W. H. L. Russell, F.R.S. 526 



XI. On the Undercurrent Theory of the Ocean, as propounded by recent ex- 

 plorers. By Captain Speatt, C.B., R.N., F.R.S 528 



XII. On the Physical Principles concerned in the passage of Blood-corpuscles 

 through the Walls of the Vessels. By Richaed Noeeis, M.D., Pro- 

 fessor of Physiology, Queen's College, Birmingham 55& 



List of Presents 564 



Index 573 



Obituary Notices : — 



William Allen Millee xix 



John Thomas Geayes xxvii 



Note, p. 526. 



I did not perceive till the eve of publication that L ;i =0 ; this will give as the equation 

 to determine Q simply, L c +L 1 ^^ + . . . +I^gS=a 



W. H. L. R. — July 31, 1871. 



NOTICE. 



With the commencement of Vol. XX. the Annual Subscription for the Proceedings 

 of the Royal Society will be Twelve Shillings. 



TAYLOR AND FRANCIS, RED LION COURT, FLEET STREET. 



