To the Honourable 
Sir ROWSRT SOVTHrELL^Kt- 
PRESIDEN T i 
And to the 
Cottnctl mti jftlloW 
OF THE ' 
Royal Society 
LONDON, 
F O R T H E _ 
Advancement of Natural Kmrpledge, 
This Seventeenth Volume 
O F T H E 
Philosophic A L Transactions 
Is humbly Dedicated 
By Richard ff^aller, S.R-S'eCF" 
