8 Geometrical Inflru^ions 



Of owsfhei and Curvillnea} Figures^ and of Figures jnixi 



'-' 'A Circle is a Figure perfectly round, drawn or 

 defcrib'd from a Letter, from which the whole Cir- 

 frumference is of equal Diftance. The Boundary 

 . Line whereof is call'd the Circumference, or other- 

 wife, the circular Line that enclofeth it. Fig. i. 

 Letter 4. . ^ , 



An Oval (tth-Ovo,m-\ Fgg) is a crooked Figure 

 drawn from m^ny Centers ^ and which Diameters 

 divide into two Equalsy Fig. 2. This is alfocalFd 

 ani Lllipfis ^ but this Word, as well as the Word O- 

 val,* is more properly apply 'd to Fig. 5. Letter B, 

 near the Shape of an Egg. 



; A Demi or S^mi-cirele or Oval, is the exa£t half 

 of a Circle or Oval, as is C D, Fig. 4. 5. 

 ci:;i ^ Quadrant of a Circle, is the exad Quarter 

 thereof , as E , Fig. 6. 



- A Segments or Part of a Circle, either more or 

 Itfs than the half or quarter of one, as is F. Fig. 7. 



.ASe6lor,or 8e£llon of a Circle,is cpntain'd with- 

 in two Diameters^ then half a Circle, as is G. Fig. 



Figures concentrical, or thofe which have one 

 and the fame Center, H H, Fig. 9. 10. 



Figures excentrical are thofe which are contain'd 

 in others of divers Centers, I I, Fig. n, 12. 



Thefe being the moft material Definitions, I 

 pafs now to the next Thing in Courfe to be knov/n, 

 which axe the J)s.jiotf^us& in Geometry. 



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