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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.

I ke Difficulty of planning the foregoing Dimensions, va-nishes when yeu consider them as two distinct Triangles, hav-ing one common Base, commonly called th c Diagonal.

Protraction.

First, At Pleasure draw the diagonal Line A C, and, byProblem IV, make the Triangle DAL; thus take from yourScale of equal Parts 14 Chains, and set it off horn A towards L,and tfiere erect a Perpendicular to the Left-hand, upon whichlay down 4 Chains, 45 Links, the first Perpendicular found ormet with in the field.

Secondly, From the fame Scale take 15 Chains, 35 Links, inyour Dividers, and lay it also from A towards C, at which Placeerect a Perpendicular also, and lay thereon 12 Chains, 10 Links,your second Perpendicular. And,

Lastly, Join the Points A, B, C, and D, together, and itis done.

PROB.