CONTENTS. 
XVI. An account of a new mode of per joining the High Opera - 
tionfor the Stone. By Sir Everard Home, Bart. V. P. R. S. 
p. 209 
XVII. A Sketch of an Analysis and Notation applicable to the 
estimation of the value of Life Contingencies . By Benjamin 
Gompertz, Esq. F. R. S. 214 
XVIII. On the measurement of Snowdon, by the Thermometric al 
Barometer. By the Rev. F. J. H. Wollaston, B.D. F.R.S. 
2 95 
XIX. On Sounds inaudible by certain ears. By William Hyde 
Wollaston, M. D. P. R. S. 30 6 
XX. Particulars inspecting the anatomy of the Dugong, in- 
tended as a Supplement to Sir T. S. Raffles’ Account of that 
animal. By Sir Everard Home, Bart. F. R. S. 315 
XXI. On the compressibility of Water. By Jacob Perkins, Esq. 
Communicated by the late Right Hon. Sir Joseph Banks, Bart. 
G. C. B. P. R. S. 324 
XXII. Astronomical Observations. By Stephen Groom- 
bridge, Esq. F. R. S. 330 
Presents received by the Royal Society, from November, 1819, to 
July, 1820. 333 
Index. 345 
