Chap. L of Gardening. 



99 



THE SEVENTEENTH PRACTICE: 



To draw a Circle upon the Ground. 



S u p p o s E the Stake A to be the Center of the Circle A 

 which you would defcribe^ meafure, upon the Plan, the 

 Diftance from the Center to the Circumference^ as from 

 a to fuppofe fix Fathom, which is the Semi-diameter ^ 

 put the Loop of a Line of fix Fathom long over the Stake fig. xvrr. 

 and the Point of a Tracing-Pin through a Loop made at the plate iv. 

 other Extremity B. Carry the Line and Tracing-Point quite 

 round about the Center A^ till you come to the Place where 

 you firft began, as which traces your Circle entirely^ 

 obferving that the Line be always fl^rained alike, that nothing 

 interrupts it, and that the Tracing-Pin be confl;antly held in 

 the fame Difpofition, without varying its Point j befides 

 which, let the Stake in the Center A be held by fome-body 

 to keep it perpendicular, left in ftraining the Line too much 

 it give way, and make the Circle bigger than that of the 

 Plan. 



Observation* 



I T is eafy to apprehend, that the Application of this Ex^ 

 ercife may ferve for tracing Half or Quarter-Circles^ and, 

 generally, any circular Segment whatfoever. 



THE EIGHTEENTH PRACTICE. 



To draw an Oval upon the Gromid. 



Let the Oval upon the Paper be whofe longeft Dia- 

 meter only is determin'd 12 Fathom ; trace out upon the 

 Ground the Line A B of 11 Fathom long, and divide it into 

 three equal Parts, where plant Stakes, as in the Points C and 

 D. Then take a Cord of the Length D 5, or C A, with 

 which trace lightly two Circles, from the Center-^Stakes 

 C and D, which Circles interfed one another in the Point 

 E andF; in thefe drive two Stakes, and the Points CD EF 

 fliall be the four Centers of the OvaL Fix a Line upon the FIG.XVIII. 



O 2 Stake 



