CONTENTS, 
XV. Researches in Physical Astronomy. By J. W. Lubbock, Esq. V. P. and 
Treas. R.S page 231 
XVI. Researches in Physical Astronomy. By J. W. Lubbock, Esq. V.P. and 
Treas. R.S. 283 
XVII. On a peculiar class of Acoustical Figures ; and on certain Forms assumed 
by groups of particles upon vibrating elastic Surfaces. By M. Faraday, 
F.R.S. M.R.I. , Corr. Mem. Royal Acad. Sciences of Paris, 8$c. 8$c. 299 
XVIII. A Table for facilitating the Computations relative to Suspension Bridges. 
By Davies Gilbert, Esq. V.P. R.S 341 
XIX. An Account of the Construction and Verification of a Copy of the Im- 
perial Standard Yard made for the Royal Society. By Captain Henry 
Kater, F.R.S 345 
XX. On the Theory of the Elliptic Transcendents. By James Ivory, A.M. 
F.R.S. Instil. Reg. Sc. Paris, et Soc. Reg. Sc. Gottin., Corresp. . 349 
XXI. On the Tides in the Port of London. By J. W. Lubbock, Esq. V.P. 
and Treas. R.S 3/9 
XXII. On the extensive Atmosphere of Mars. By Sir James South, F.R.S. 
Communicated by His Royal Highness the President 417 
XXIII. On the Friction and Resistance of Fluids. By George Rennie, Esq. 
V.P.R.S 423 
