CONTENTS OF VOL. XXXIII. 



(FOURTH SERIES.) 



NUMBER CCXX.— JANUARY 1867. 



Page 



Dr. E. J. Mills on Isomerism 1 



Archdeacon Pratt on the Figure of the Earth, as obtained from 



Geodetic Data 10 



Dr. A. Topler on the Application of the Principle of Strobo- 

 scope Disks to the Optical Analysis of Vibrating Bodies. 



(With a Plate.) 16 



Mr. C. M. Willich on the Partition of the Cube, and some of the 



Combinations of its parts 27 



M. L. Schwendler on the Galvanometer Resistance to be em- 

 ployed in testing with Wheatstone's Diagram 29 



Dr. E. C. O. Neumann on an Apparatus for directly measuring 



the Velocity of Sound in the Atmosphere. (With a Plate.) 36 

 Prof. J. Plateau's Experimental and Theoretical Researches into 

 the Figures of Equilibrium of a Liquid Mass without Weight. 



— Seventh Series 39 



Prof. Sylvester on the Multiplication of Partial Differential Ope- 

 rators 48 



Dr. Atkinson's Chemical Notices from Foreign Journals .... 56 

 Proceedings of the Royal Society : — 



The Rev. T. R. Robinson on the means of increasing the 

 Quantity of Electricity given by Induction-machines. , . 63 

 Proceedings of the Geological Society : — 



Mr. P. M. Duncan on some Echinodermata 73 



Mr. J. C. Hawkshaw on the First Cataract, Upper Egypt . . 74 



Mr. J. Curry on the Drift of the North of England 74 



Observations by a new Optical Method, by Dr. A. Topler .... 75 

 Observations on certain Lines of the Solar Spectrum, by M. 



Angstrom 76 



Remarks on the above communication, by M. Janssen 78 



Note, by Messrs. De la Rue, Stewart, and Loewy, on the Distri- 

 bution of Solar spotted Areas in Heliographic Latitude 79 



NUMBER CCXXI.— FEBRUARY. 



Mr. G. Forbes on the Meteoric Shower of the 14th of Novem- 

 ber, 1866. (With a Plate.) 8i 



