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Geodaesia improved; or, a new and correct method of surveying made exceeding easy in two parts : part I. Teacheth to measure, divide, and delineate, any quantity of land both accessible and inaccessible, whether meadows, pasture, fields, woods, water, commons, forests, manors, &c. by the chain only, whose dimensions are cast up by the pen, and consequently freed from the errors of estimation that unavoidably attend the scale and protractor. With necessary directions to map elegantly : part II. Introduces instruments, trigonometry, preparative remarks on the earth's superficies; and teacheth the invaluable method of casting up the dimensions of instruments by the pen several ways, all agreeing, &c. &c. : with a most useful appendix concerning the practical methods of measuring timber, hay'marl pits, bricklayers and plasterers work... / A. Burn
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GEODÆSIA Improved.

Example II.

Let it be required to extract the Square Root of 160, or,which is the fame Thing, to find the Length of one Side of asquare Acre.

See the Work.

> )i6o(I2, 64911

I

22) 6044

246)1600

1476

12400

Having pointed the given Number, and wrought as before di-rected, you find 12 for your nearest Root, and 16 to remain, towhich you add two Cyphers, and find your next Figure to be 6,which you must cut or point off from the rest, as a decimalFraction; and by adding Pairs of Cyphers to each Remainder,as below, you increase it to 5 Places, which is exact enough forany thing; for if Unity were divided into a hundred Thousandequal Parts, this Root does not want 2 of those Parts ; since theSquare of 11.64911, is 159 9999837921.

2524)12400(12.64911

10096

25289)230400

227601

252981)279900

252981

2529821)2691900

2529821

remains 162079

Thus