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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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jgz GEODÆSIA improved.

of Sines, Tangents, Secants, ctsV. A!so, for Projection, theLine of Chords (used in making and measuring ot Angles,)Line of Tangents, and Semi-tanaents, Rum-lines, &c. Theselatter we shall have no Occasion for in this first Part.

Exclusive of the above-mentioned Scales, there are otherswhose Lines are differently divided ; namely, the Inch dividedinto ii, 12, 16, &c. equal Parts, I don’t look upon such Scalesrobe (o particularly adapted to the Chain as the first mentionedScale, notwithstanding a Person may plan by, or from anyScale divided into equal (vulgar fractional) Parts. But those whichI would recommend, are the Inch, half Inch, &c. decimally di-vided, as the easiest and most ready for a Learner.

Directions to use them.

Scales of equal Parts, are for measuring or laying downLines, and are differently made and divided, if the i, 2, &c.be accounted no more, the Sub divisions at the End and Topare 1 decimally divided into Tens, and Hundreds.,

But if the 1 be reckoned 10, the 2, 20, &c. whether upon theInch, half Inch, or quarter Inch, the Sub divisions are Chains,and tenth of a Chain, that is, 10 Links : And when you callthe 1 or 2, &c. 100 or 200, &c. the Sub divisions at the Toprepresent ten Chains each; and those at the End 1 Chain; so eInstance; if it were required to take 370 Chains off the Scale,set 1 Foot of the Divider.- in 3, (whether Inch, half, or quarterInch, it is not material, so that it be the Scale you propose toplot by,) and the other f oot in the seventh small Division atTop, and that Ex ent will contain 370, which is the same Dis-tance that represents either 3 Chains, 70 Links, or 37 Chains:But here every large Division, where the Numbers 1, 2, 3, &c.are placed, are accounted 100, viz 1 is 100, 2 is 200, &c.and then every small Division at Top is 10, and each one at theEnd, represents I Cnain only; and in this Case, if there beanyodd Licks, you must compute them between the Sub divisions,as suppose )ou muset oft 81 Chains, 38 Links, set 1 Foot in8, and extend the other to the first small Division at Top, asif you were to set off 81. and that represents ,8z .00, or 81 Chains;then shift both Legs of the Dividers almost 4 Divisions at the

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