72 HISTORY of the SOCIETY. 







^ r STEWART'S conftant ufe of the geometrical analyfis had 

 put him in poffeflion of many valuable proportions, which did 

 not enter into the plan of any of the works that have been 

 enumerated. Of thefe, not a few have found a place in the 

 writings of Dr SIMSON, where they will for ever remain, to mark 

 the friendship of thefe two Mathematicians, and to evince the 

 efteem which Dr SIMSON entertained for the abilities of his pupil. 

 In the preface to his Conic Sections, in which he acknowledges, 

 that all the theorems, diflinguifhedby the letter x, were commu- 

 nications from Dr STEWART, he calls him, " egregix indolis et 

 " peritise virum ;" and in that to his Porifms, after pointing 

 out many proportions that had been fuggefted by PAPPUS, 

 and a few that had been adopted from, PERM AT, he adds," Alia 

 " quasdam adjecta funt quorum praecipua mihi propofuit, et 

 " aliquorum conftrudlionem dedit eximius Geometra MAT- 

 " THJEUS STEWART, a quo materia hsec jam egregie eft ex- 

 " culta, poftea, ut fpero, multum excolenda." 



THERE is alfo a theorem of Dr STEWART'S publifhed in Dr 

 SIMSON'S edition of EUCLID'S Data, which I take notice of, 

 chiefly as it affords me an opportunity of paying a tribute to the 

 memory of a man, whofe high rank did not prevent him from 

 cultivating a fcience, which it enabled him to patronize. In the 

 note, where Dr SIMSON acknowledges that communication, he 

 mentions another theorem, alfo publifhed among the Data ', 

 " Thefe proportions (fays he) were communicated to me by 

 " two excellent Geometers, the firft by the Earl STANHOPE, the 

 " fecond by Dr MATTHEW STEWART." 



To this Nobleman, for whofe abilities and worth Dr STEW- 

 ART entertained the higheft refpect, he made a vifit in 

 the courfe of a tour through England, foon after the pub- 

 lication of the Effay on the Sun's Diflance, and received 

 from him very fingular marks of attention. At a later pe- 

 riod, when he lamented the lofs of Dr SIMSON, he had the 



confolation 



