jv 



ASTRONOMICAL PAPERS. 



'33 



henftve that he Jhould leave Philadelphia before my return. 

 I then recolle£ied tvhat you had told me fame time before^ 

 eonccrning your improveinent of Godfrey's quadrant, and 

 fpoke to Mr. Grant as follows : I amjorry, I am obliged to 

 go out of town to morrowy as I could ivifh to have fame 

 further converfation on this fubjeSl\ but there is a gentle- 

 man of this city^ the Rev. Mr, Ewing^ ivhofomc time a^jo 

 mentioned to me an improvement of ajimilar nature^ vuhich 

 he had made-^ and I believe he has engaged a workman to 

 finifJd a quadrant for him^ on the plan he has pro] elded. 

 Are you acquainted %vith Mr. Ewing ? If not ^ Ixvillhring 

 you together^ for I voouldvuiflj you to compare yonrfchemes^ 

 and to have^a conference with each other. Mr. Grant ex-- 

 pref]ed his defre to be acquainted with Mr. Ewino-, and / 



accordingly introduced them to each other., before I went 



WILLIAM SMITH.'' 



on my journey. 



To the Rev. Mr. Ewing. 



Thefe things I have mentioned not from a folicitude a- 

 bout the invention, but to fliew, that, what has often been 



fuppofed probable in affairs of this nature, has adually 

 taken place in the prefent inftance; that men at the diftance 

 of many thoufand miles might fall nearly upon the fame 

 inventions, about the fame time, without any previous 

 correfpondence or acquaintance with each other. T. E. 



An ESSATontheUfe of COMETS, and an Account of their 

 Luminous Appkarance; together with fome Conjee-- 

 tures concerning the Origin of HEAT. 



By H U G II WILLIAMSON, M. IX 



Read bif ore the Society^ Nov. i6thy lyyo. 



M 



g round the 



Sun in flalcd periods^ receiving light and heat from, 

 the Sun. Comets revolve as other planets do in an ellipfis, 

 Vol. L S one 



