Mifcellanea Curt of a. I ox 



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^ Difcourfe concerning the Num* 

 her of Roots, in Solid and Bi- 

 quadratic al Equations, as alfo of 

 the Limits of them. 



By E. Halley. 



HAving in the precedent Difcourfe Ihewn 

 a Method, by which folid Problems 

 however affected, might be conftru&ed after 

 a moil fimple and eafy manner, by the help 

 of one. given Parabola and a Circle } towards 

 the latter end a certain pleafant Speculation 

 pffer-d it ftff, namely, that from thefe Con- 

 ftru&ions, the Number of Roots in any E- 

 quation, with their Limits and Sines, would 

 eafily follow and be determined. Upon which 

 account, I promis'd that I would quickly 

 write a fhort Differ tat ion concerning this 

 Subjefr, in which I was perfwaded I mould 

 perform fomething not unprofitable nor un- 

 grateful (if not to the Geometers of the 

 firft, yet at leaft) to thofe of the lecond 

 Rank. 



But coming to look nearer into the Bull- 

 nefs, I found I was imprudently fallen in 

 among fome of the profound Difficulties of 

 Geometry, and deftin'd to handle the fame 

 Things, that formerly employ'd the Pains 

 of two Illuftrious Men, Harriot and Cams; 



H 3 in 



