PHILOSOPHICAL 
TRANSACTIONS, 
OF THE 
ROYAL SOCIETY 
OF 
LONDON. 
FOR THE YEAR MDCCCXVII. 
PART II. 
LONDON, 
PRINTED BY W BULMER AND CO. CL EVE LAND-ROW, ST. JAMES’S? 
AND SOLD BY G. AND W. N1COL, PALL-MALL, BOOKS ELLERS TO HIS MAJESTY, 
AND PRINTERS TO THE ROYAL SOCIETY. 
MDCCCXVII, 
