Book IV. TRANSFERRING DESIGNS TO PLANE SURFACES. 



373 



principal parts {jig. 355.), as seen from some elevated conspicuous hill, building, or 

 object near it ; or if the estate, as is frequently the case, is situated on the side of a 

 hill, or range of hills, a situation on the plain, or flat grounds opposite to it, will be 

 sufficient. 



355 



1912. Great improvements have been made in the art of delineating estates by T. Hornor, 

 an elegant and scientific chorometer and draughtsman. See his Mode of Delineating 

 Estates, 8vo. 1813; and Lehman's Topographical Plan Drawing, oblong fol. 1822. Mo- 

 dels of estates are also formed in cork, papier machee, and other substances, which 

 for hilly scenery are very useful and entertaining. 



Sect. II. Of transferring Designs from Paper or Memory to Ground. 



1913. Staking or marking out plans is a subject requiring much greater skill than the 

 last, on account of the inequalities and other obstructions met with on the ground's 

 surface. It may be considered, 1. As to transferring figures to plane surfaces; 2. To 

 irregular or obstructed surfaces ; and, 3. Arranging quantities. 



Scesect. 1. Transferring Figures and Designs to plane Surfaces. 



1914. The transferring of plane or regular figures to even ground is nothing more than 

 performing the elementary problems of geometry on a large scale. The subject has been 

 amply illustrated by Switzer, Le Blond, and other writers of their day ; but a very 

 few examples will here suffice, as the school education of gardeners is now superior to 

 what it was in those times. 



1915. A perpendicular to any line 356 

 may either be found by taking a 

 garden-line, doubling a portion of it, 

 and applying the extremities at equal 

 distances from the point whence the 

 perpendicular is to proceed (fig. 

 356. a) ; or more simply, but on a 

 large scale with less accuracy, by 

 applying the garden-square (b), or 

 on any scale by the use of a rope 

 or line united at the extremity, and 

 divided in the proportions of 6, 8, 

 and 10 (c). The 6 is to be placed 

 as the perpendicular of a right-angled 



triangle, the 8 as the base, and the 10 as the hypothenuse ; or three rods of similar 

 proportions, or divided into feet, and the proper numbers taken, may be used for this 

 purpose. Switzer informs us this was the mode in which all right-angled figures in 

 gardens, and all other works, were set out in his time. 



1916. To divide an angle, a line united at the extremities, and divided into four equal 

 parts (d) , may readily be so applied to any angle as to divide it equally or the same 

 thing may be done by a portion of line bisected, and its extremities applied at equal 

 distances from the angle (e). A line divided into three equal parts readily forms an 

 equilateral triangle (fig. 356. f). 



1917. To describe an oval within a given length, the length may be divided into three 

 equal parts ; then let the two inner points so found be the centres of two circles which 

 shall form the ends of the oval, and the sides may be formed by segments whose centres 

 are the intersecting points of the circles (Jig. 357. a). The same oval may be formed by 



Bb 3 



