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from A to Chen take from your Scale the Length of the Line AB 7. eo, and put one Foot of your Compaffes in A, with the other defcribe the Arch a a; then take the Length of the Line BC 6.00 from your Scale; placing one Foot in C, with the other cross the former Arch in B, as bb, this done draw the 2 Lines AB and BC.
Second, Take from your Scale the Base Line CE 8.00, and placing one Foot of your Compaffes in C, with the other defcribe the Arch ee, then take with your Compaffs the Length of the Bafe Line EA 5.80, fetting one Foot in the point A with the other crofs the former in the point E, as ff, which point E is the meeting Agleto both the other 2 Ang'es.
Thirdly, For the protraction of the Triangle CED, take from your Scale the Line CD 3. 10, placing one Foot of your Compaffes in C, and with the other make the Arch cc, then take the Length of the Line DE 5. 15, and fetting one Foot in E, with the other cross the former at D, as dd, from which Interfction draw the 2 Lines CD and DE.
Leftly; For the Triangle AF, take with your Compaffes FF 2.15, placing one Foot of your Compaffes in E, with the other ftrike the Arch hh, then take AF 400, fetting one Foot in A, and with the other crofs the former Arch in F, draw Lines therefrom,
as from A to F, and from F to E, fo have you protracted your Plot upon Paper, as was required.
And you muft be careful to note down. the Scituation of the Angles, viz. inward and outward, for fear of committing of a miftake when you protract the fame.
Now if you draw a Line from C to F, you divide it into 2 Trapeziums; and then the Content is found as hath been before taught.
How to take the Plot of a Field by going round the fame.
Fig. Let ABCD reprefent a Field to be measured. Firft beginning, at the Angle A, I measure one Chain in Length towards B, as to a, and another towards E as to b; next, I take the diftance from a to b 1. 50, and note it down in my Field Book, for the Quantity of the Angle A and measure the Hedge AB 3.00, and put it in my Field
Next I come to the Angle B, and meafuring one Chain to d, and another to c, I take the diftance dc with my Chain, and I find it to be 1. 40, and the Hedge BC 3. 15. Next I come to the Angle C, and meafuring one hain to e, and another to f, and take the diftance fe, I find it to be 1. IC, and from C to D, 2. 17, and fo I pro
ceed till I come to the Angle A; and I find
to be as follows.
First, I take from my Scale 1 Chain, and having drawn a L... as AB, upon A as a Center, I ftrike he Arch a b; then take from your Scale 10, and fet it from a to b, and draw the Line AE, fetting thereon 2. 60 from A to E, and 3 Chains from A to B; then taking one Chain from my Scale and putting one Foot in B. I ftrike the Arch c d; next I take 1 Chain 40 Links, the Quantity of the Angle B, and fet it from d to c, and draw the Line BC, making it to be in Length 3. 15. Next I come to the Angle C, and fetting one Foot in C, with the other I defcribe the Arch ef, then tak ing 1. 10, from your Scale, I fet it from e to f, and through the point f, I draw the Line CD in Length 2. 17. Next I come to the A-g'e D, and always taking 1 Chain from my Scale, I put one Foot in D, and with the other defcribe the Arch on; then
taking 1 Chain and 80Links, I fet it from o to n, and the Line DE, which Line muft juft meet the end of the Line AE and contain in Length 2, 80. if your Work be well done.
I inuft acknowledge that this fort of Plotting of Parcels of Land that have many Arges,requires not only more care and pains; but better Skill and Memory than to draw Diagonals upon Paper, when the Plot is already taken by the plain Table. I fhall therefore give you fome ways to help your felf, fo as to be out of danger of Miftakes.
One way is, to divide a MultangularField into 2 or more parts, then might each part be measured feverally, as if they were feveral Mens Lands parted by a Boundary.
Another way, which much helps the Memory and Underftanding, is to draw a rude Draught of the Figure of the Lands you intend to measure, not only as to the fides, but also the Dagonals: Then measure the Lines upon the Ground correfpondent to thofe on the Paper, and fet the Lines as you measure them, upon the Sides of your Draught, as if they were the true ones, and when you have finished your Measuring,prctract it truly, and it will do your Bufinefs.
How to tak: the Plot of a Field from one Station taken in the middle thereof, by the Chain,
Fig. 91. Let ABCDE reprefent the Field to be plotted: firft at K, I fet down a Stick, then Measure one Chain in Length towards A, as K o, and alfo the Length of the whole Line K A, which note down upon your rude Draught: Next measure one Chain in Length towards B, as K p, and alfo the Length of the Line K3; and note it on your foul Draught: Next you must measure the diftance betwixt o and p, and fo place it down upon your Draught.
And fo I measure one Chain in Length towards C, as R q, and alfo the Length of the Line KC, and note it down upon my rude Draught, as alfo the diftance pq: And fo I proceed round the whole Field, and find them to be as is noted in the Fi gure following.
Hw to Protract this Work.
First take from your Scale one Chain in Length,, then upon K as a Center, describe the Circle o p q RS; next take from your Scale pq 2 Chains, the Length of the Line KA,and fetit from K to A Next take from your Scale 172 Lin, and fet it from o till it touch the Circle in p, and through the point p, draw the Line KB, making it to be in Length 215: