jMifcellanea Curiofa. 



j4 ^Dijfertatipn concerning the Con- 

 JiruSion of Solid c Problems< ) or 

 Equations of the third or fourth 

 c Poisoer^ by the help of one (given) 

 parabola and a Circle. 



By Edmund Halley, 



HOw all Equations (that involve the third 

 or fourth Power of the unknown Quan- 

 tity) may be conftru&ed by the help of any 

 given Varahola and a Circle^ the Famous M. 

 Des Cartes has (hewn and clearly demonftrated 

 in the Third Book of his Geometry. But he 

 fir ft of all orders the fecond Term of the E- 

 quation (if it be there) to be thrown out, and 

 then by the Rule there delivered, to find the 

 Roots of the Equation fo reduced. 



And iince that Operation feems too La- 

 borious, fome thought fit to invent a like 

 Conftru&ion, without any previous Reduction. 

 Amongft whom Francis a Schooten has ofFer'd a 

 Method ( for co'nftrucling cubical Equations 

 howfoever affected J which might have been 

 called very eafie and fimple ; if ("by unfold- 

 ing the Principle from whence he deduced his 

 Rule) he had better confulted his Reader's 

 Memory, which he burdens with very many 

 and perplex'd Cautions. But lately our Fa- 

 mous Countriman, Mr. Thomas Baker^ in a 

 whole Treatife written upon thefe Confltu- 



ftionsj 



