ifg The Statural Hiftory 



ncrally received n , and what kind of new notation muft be intro- 

 duced to exprefs it, with divers methods of fquaringthe Circle, 

 Ellipfis, and Hyperbole, fo far as the nature of Numbers will bear , 

 having apply 'd his method of Infinites in order thereunto ; as alfo 

 for rectifying of Curve-lines, plaining of Curve -fur faces, fquaring 

 of innumerable forts of Curve- lined figures, plain and folid (a- 

 mongft which are a multitude of figures of infinite length, andyf- 

 nite content) determining their Centers of Gravity, and other ac- 

 eidents, 



198. He has alfo adjufted the ftrength of percuffions and reflexi- 

 ons (or repercuffions') and other motions to Geometrical meafures, 

 deduced from principles of Elafiicity ; and has eftimated the ar- 

 tificial force acquired in all forts of Mecbanick Engins, deduced 

 from our common principle of the Reciprocation of Strength and 

 time ; with many other improvements of Aritbmetick, Algebra, 

 Gtometry, Methanicks, and other parts of Matbematicks, in his 

 Arithmetic^ of Infinites, his Treatife of the Cycloid, with that ad- 

 joyned of the reclificat ion of Curves ; his Treatife of Motion, and 

 other his Printed Works. 



199. In Muftck. (which is Aritbmetick adorned with founds) 

 to pafs by a Harpfechord 'that I met with at Sir Tbo. Penyfions with 

 Cats-gut ftrings. It hath been lately obferved here at Oxford, that 

 though Viol or Lute ftrings rightly tuned do affect one another, 

 yet moft of them do it not in all places alike, as has till now been 

 fuppofed : for if the leffer of two Oftaves be touched with the 

 hand or bow, each half of the greater will anfwer it, but will 

 ftand ftill in the middle ; and if the greater of the two Raves be 

 touched on either of its halves, all the leffer will anfwer it, but if 

 touched on the middle, the leffer will not ftir any where at all. So 

 if the leffer ftring of two fifths be touched on either of its halves, 

 each third pzrt of the greater will anfwer it, but if on the middle 

 they will not ftir ; and if the greater of two fifths be touched on ei- 

 ther of its thirds, each half of the leffer will anfwer it, but if in 

 the divifions they will not ftir : and foof twelfths, fifteenths, istc 



200. Which Phenomena I fhall always gratefully acknowledge 

 were firft difcovered to me by the ingenious Thomas Pigot B. A. 

 and Fellow of Wadham College, which have alfo been obferved for 

 about thefetwo^r^by the no lefs ingenious William NobleU. A. 



* Vtd. Aritl:tn:ticamInjinitorum,Prop.\^, cttmSchtliofetpi. 



of 



