( Kum. i$ 6 
PHILOSOPHICAL 
TRANSACTIONS. 
Mimday , Auguft 6. 166', 
The Contents. 
An E/fay of Dr. John Wallis, exhibiting his Hypothefis about the 
Flux and Reflux of the Sea, taken from the Confideration of the 
Common Center of Gravity of the Earth and Moon 5 toge- 
ther with an Appendix of the fame , containing an Anfwer to 
fome Obje&ions, made by feverall perfons againfl that Hypo- 
thefis. Some Animadverfions of the fame Author upon Mafer 
Hobs's late Boo\, De Principiis & Ratiocinatione Geome- 
trarum. 
An Effay 
Of Dr. John Wallis , exhibiting bis Hypothefis about the 
Flux and Reflux of the Sea. 
iOw abftrufe a fubjeft in Philofophy , the 
? Flux and Influx of the Sea hath proved hi- 
therto, and how much the fame hath in all 
Ages perplexed the Minds even of the beft 
oiNaturalifts , when they have attempted 
to render an Account of the Caufe there- 
of, is needlefs here to reprefenr. It may 
perhaps be to more purpofe,to take notice , that all the defici- 
encies, found in the Theories or Hypothefes , formerly invented 
for that End , have not bee$ able to deterre the Ingenious of 
this Age from making farther fearch into that Matter : Among 
whom that Eminent Mathematician Dr. John Wallis , following 
his happy Genius for advancing reall Philofophy, hath made it 
a part of his later Inquiries and Studies , to contrive and de- 
duce a certain Hypothefis concerning that Hftnomemn^ taken 
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