PHYSICAL AND LITERARY iit: 



DFM equal to the fedor DFG: but the 

 other way points out the method of cal- 

 culation. 



PROP. IV. FROhL.2. R'g.4. 



Let there be a femiclrcle whofe dia- 

 meter is AB and center C, -and let 

 D be a point in the diameter : 

 granting the quadrature of the cir- 

 cle, it is required to draw a line DE 

 meeting the circle in E, fo that the 

 femicircle may be to the fe6i:or 

 BDE in a given ratio, fiippofe that 

 of ^ to ^. 



Suppose the problem folved. Let the fe- 

 micircle be to the fedor BCF as /> is to q ; 

 join DP J draw CG parallel to DP, meeting 

 FG, a tangent to the circle at F, in G, and 

 join DG meeting the circle in H ; let CG 

 meet the circle in K, and join DK, PK, CH. 



Because the femicircle is to the fedor 

 BDE as/> to^, that is, as the femicircle to the 



fedor 



