A 



TABLE 



OF THE 



Difcourfes contained in this 

 Volume. 



N Eftimate of the Quantity of Vapours 



X JL Experiment: Together with an Account 

 of the Circulation of the wafry Vapours of the 

 Sea, and of the Caufe of Springs. Prefented to the 

 i\oyal Society by Mr.E.Halley, F. S. Pag. I. 

 The True Theory ef the Tides, extracted from that 

 admired Treatife of Mr. Ifaac Newton, Intituled 

 philofophise Naturalis Principia Mathematica ; 

 hein? a Difcourfe prefented with that Book, to the 

 late K! n $ J ames > h Mr - % Halley. 1 3 



A Theory °f the Variation of the Magnetical Com- 

 pafs, byMrM. Halley. *7 

 An Account of the Caufe of the Change of the Va- 

 riation of the Magnetical Needle, with an 



l\JU vj '~o - 



mhefis of the Structure of the Internal 



raifed out of the Sea, as derived from 



Parts 



