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And likewife through c, and d, and where thefe Lines Interfect gives you the very corner at x Next from the point C, prick off 2 c.50 l. and at right Angles to the point at 26. 50l. prick off I c. 20l. to the Hedge at g, and draw the black Line gf: Next from the point C: prick off 3 c. 90. l. and at that distance prick off I c 40l at right Argles, to the Hedge at h, and draw the Black-line h g,then from the point C prick off 6 c. 30l. to the Station at D; at this Sa-. tion D prick off 80 Links to the Hedge at c, and 50 Links to k, both at right Angles: At the Station D prick the Quantity of the Angle CDE with your protractor, which contains 75° 30 then from the point D, with your Scale prick cff 3 c. 601. and at right Angles to this Mark laft fet off, prick. off Ic5, to the Angle at C, and draw the Lines 1k and hi, till they interfect. each other, which will give you the corner at z. At the Station D. Prick off 8 c. 151. from your Scale of equal parts, and at right Angles to this laft Mark prick off 1 c. 50 1. to the Angle at m; and draw the Blackline m 1. At the Station D, prick off" upon the Line DE 13 c. 20l. to the Station at E; from this Station prick off 30 Links at right Angles to the Hedge at n,and 30 Lin. to the Hedge at o; at the point E protract the Quantity of the Angle DEF with your protractor, which contains 99° : oʻthen
from the point E prick off 4c 10 l. where it touches the Hedge at p, then prick off 8 c. 30 1. to your Station at F. prick off at the point F 50 Links at right Angles to the corner at g, then draw the Black-lines Pq pc. Likewife draw the Black-lines m n; where the two Lines m n and p o Interfect gives you the very corner of the Field at y: at the point F, protract the Quantity of the Angle EFA with your protractor, which contains 10 8° 3'o, and if the Line FA falls in the point A; your work is right fo far: From the point F prick off 2 c. 70 l. from which point prick off at right Angles 85 Links to the Angle at s; then from the point F prick off 6 c. 651. and if 6 c. 651. reaches juft to the point A,y cu may be affu:ed your Survey was taken truly. To enclose your Field draw the Black-line from q s, and from s to a, the line cb and fabeing continued, will interfect at w, the very corner which enclofes your Field.
N. B. As I have recommended in this Example the thin Ruler with equal parts, upon the very Edge to protract with, being much better than Compaffes on many Accounts, as every Surveyor will find. So I wou'd advife every Surveyor, that is curious, to make ufe of Mr Ward's Protractor improved: The Semi-Circle is made near as ufual; upon this Semi-Circle is moveable Index of 7 Inches lorg, the upper
part being 5 degrees from the Center, and the lower part next the Limb; 4 Degrees, fo that each Edge will be Diagonal of one deg. upon this Edge is unequal Divifions Calcu lated to every Minute. This Defcription is according to Mr Wards, inftead of having the Index thus made, I think it much better to have that part of the Index above the Limb to be part of an Arch of two degrees, and the other part fuppofed to pass thro' the Centre: Now upon this Index the Divifions will be equal, and will be confiderably larger at the beginning of the Divifions than in the other. The Demonftration of this depends upon Theo. 13 where 'tis proved that the Argle at the Center is double to that at the Circumference. The ufe of this Inftrument is very easy for you have no more to do but to fet the Index to the whole degrees obferved, and upon the Index graduated, prick off the Minutes: This Protractor with Scales, as before mentioned, with all forts of Mathematical Inftruments, are inade and fold by Benjamin Scot (who ferved his time with Mr Rowley,) he keeps a Shop at the Mariner and Globe over against Exeter Change in the Strand.
Having now recommended proper Inftruments for protracting your Obfervations, I cannot avoid acquanting the Reader, that the beft Inftrument to take Angles, is the