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To PLOT THEM.

Draw the trapezium ABCD, and the offsets as before directed. Mark the place on the diagonal where you croffed the fence, which stands thus in the Notes: ftraight 1000 ftraight.

The words ftraight, denote the fence croffed runs ftraight to the end; and as it is croffed in more than one place, there is no occafion to meafure it unless to prove the work.

The Plot will then appear thus:

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Which being cleared of the fuperfluous marks, &c. will be finished as in the first figure.

Find the area of each Field feparately, by straightening the fences, &c. as before directed.

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It must neceffarily follow, the larger number of Fields there are, the greater will be the variety of memorandums and marks. It is impoffible to invent a method that will fuit all kind of Inclofures; but those who study these notes, and carefully lay down the pieces from them, may gain fuch a general knowledge of this method, as will enable them to furvey by it.

Most furveyors keep their Field-books in a fimilar manner, but each adopts his own marks, nor do any two follow the fame method exactly.

PROMISCUOUS DIRECTIONS.

BEFORE the learner attempts to furvey several Fields together, he ought carefully to examine the following notes, and lay down all the work from them.* When he does make the attempt, he must not burthen his memory with too many lines at first. After a little practice he may lay down the work twice a day, when more expert once a day will do. He must not be difcouraged if his lines will not prove, small variations will always occur with the most accurate, and a Tyro will very frequently have to measure his lines twice. He must not be in hafte to begin, but must walk over the tract of land two or three times, and obferve how it can be divided into the largest triangles; for in all furveying with the chain, whether of fingle or more Fields, or of a Parish, a chief point to be observed is, to measure the largeft poffible triangles which the cafe will admit. On the laying down of which triangle, the accu

* To render this as eafy as poffible, the notes for the two following examples are engraved from the real Field-book, and ftitched into covers by themselves.

racy of almost every part muft in a great degree depend.

In measuring long lines, when the mark which is to be measured to cannot be seen, great care fhould be taken to go in a ftraight direction; to do which, the follower fhould always have at least three poles before him in a straight line. So foon as he comes up to the neareft, he must direct his affiftant to get in a straight line with the other two, and fix another beyond the laft, proceeding in this manner till the line is finished, which most likely will be either on the right or left of the mark measured for.

Or fix all the poles up firft and then measure.

Suppofe two lines of a triangle AB and BC are measured, and in measuring the third line it ends at D, measure the distance from D to A, the notes will ftand thus:

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