New Principles of Gardening. 5 
PracticE. With any Interva! on / defcribe the Arch 2/2, 
make 2/ equal to 42, and with the fame Opening on # defcribe 
the Arch zmuo, make 20 equal to thrice 47, draw o4, and 
’ewill be the Perpendicular required. 
Thirdly, From q raife the Perpendicular @ v. Fig. VII: 
Practice. With any Interval of your Compaffes place 
down ata Venture one Foot thereof as at s, and with the other 
defcribe the Arches x x and ww; lay a Ruler from 7 to s, 
and “twill cut the Arch ww in ¢; join 79, and ’tis the Per- 
pendicular required. 
Fourthly, From a, Fig. VIM. raife the Perpendicular ac. 
Practice. Draw a Right Line, as de, and open your rig. 1x: 
Compafles to. any {mall Diftance, as from 1 to2, and thereon 
prick off ten of thofe Divifions: Take eight of the faid Divi-. 
fions, and place it from ato 4, with the Interval of 6 on @; 
defcribe the Arch ff; and with the Interval of 10 on 4, the 
Arch gg, croffing the former in ¢; join ¢4, and ’tis the Per- 
pendicular required. 
When Perpendiculars are to be raifed from an Angular 
Point, (as #m from #,) open your Compaffes to any Interval, 
as 2b, and onthe Angle # defcribe an Arch, as g4; then open- 
ing your Compaffes to any greater Diftance, as go, on g de- 
feribe the Arch 77, and on / the Arch 00, croffing the former. 
in m; draw wm, and ’tis the Perpendicular required.. 
PROBLEM. VIL 
O divide a Right Line into two equal Parts, by a Right Fig. VU: 
Line, asab 6y nm. | 
Practice. Ona, with any Interval greater than a2, de- 
{cribe an Arch,-as dd, and with the faine Opening on. 4, the: 
Arch ¢¢, erofling the firft in »m; from which Points draw 
the Line #m, and ’twill divide 24 in the Middle; for nb ie 
3 equal. 
