The practical surveyor, or, the art of land-measuring, made easy ... / By Samuel Wyld.

  • Wyld, Samuel
Date:
1725
Catalogue details

Licence: Public Domain Mark

Credit: The practical surveyor, or, the art of land-measuring, made easy ... / By Samuel Wyld. Source: Wellcome Collection.

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    Let Figure ^ be luppos’d toreprelent a Piece of Land, bounded with the four Strait Lines a b, b d7 d c> and c a, whole Lengths are each ten Chain, then the Area or Superficies thereof will contain ten times ten Square Chains, or ten Acres, (as per Fig-) each of the final! Squares reprelenting one Square Chain. But before the Plan of any Piece of Land can be laid down (or protracted) on Paper, in order to make a Computation of the Area or Quantity of Superficies it contains, ’tis necefiary we ihould know the Length and Pofition of the ieveral Lines that bound the lame. And to find the Length and Pofition of Lines in the Field, we make ule of Instruments, viz. To mealure the Length of Lines in the Field, we uie Gunter s Chain, containing in Length four Poles or 66 Feet, divided into ico Parts or Links, each Link being 7 Inches, and ,11 of an Inch, and a Staff whole Length is equal to x~ part of the Chainthat is to lay, 10 Links, or 6 Foot 7 Inches ,§ of an Inch. For Roads the Wheel. Inflruments us’d for taking the Pofition of Lines, are of two Kinds. With fome we take the Pofition of a Line by the Angle which it makes with the Meridian, ufins a Box and Needle, as the Circumferentor, and this is ulually call’d the Bearing of the Line. With others we take the Pofition by the Angle that the Line makes with any other given in Pofi¬ tion ^ as with the Limb of the Theodolite, the Chain, &c. But with lome we take the Angle it lelf as with the Plain Table, &c. All other Instruments either difer from thele only in Name,, or are contain’d in them. The
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