[ 428 ] 
Sir Ifaac Newton Kn c . in his Opticks printed 
in 4 0 . at London 1704, gave a table of the fpecific 
gravities of feverai diaphanous bodies. The experi- 
ments were made by him with a view chiefly to 
optical enquiries, and to enable him to compare 
their denfities with their feverai refractive powers : 
we may therefore be well allured that they were 
made by the great author with the molt fcrupulous 
care and exa&nefs. The table confifts of 22 articles. 
John Harris D. D. in his Lexicon Technicum , 
firft printed at London in 1704, fol. republilhed at 
large the feverai tables of fpecitic gravities of the 
Oxford Society and I. C. from the Thilofophical 
Tran faff ions , and that of the honourable Robert 
Boyle from his Medicina hydrojlatica , to which 
laft he alfo added fome experiments of his own, 
made as it feems with good accuracy. Thefe are 
here extracted, and placed under his name in the 
following tables. 
Mr. John Ward of Chefter , in his Toung Mathe- 
maticians Guide , firft printed, as I take it in 1706, 
acquaints us, that he had himfelf for his own latif- 
faction, made feverai experiments upon the different 
fpecific gravities of various bodies ; and that he was 
of opinion, that he had obtained the proportion of the 
weight that one body bears to another of the fame 
bulk and magnitude, as nicely as the nature of fuch 
matter, as might be contracted or brought into a 
lefter body (viz. either by drying, hammering, or 
otherwife) would admit of. And he has accordingly 
2 given 
