The compleat surveyor containing the whole art of surveying of land by the plain table, theodolite, circumferentor, and peractor ... : together with the taking of all manner of heights and distances, either by William Leybourn.

Of M^r. RATHBORNS Chain.

THe Chain which Master Rathborne ordinarily used (as himselfe saith) contained in length two Statute Poles or Perches, each Pole containing in length 16½ feet, which is 198 Inches, then each Pole was divided into 10 equall parts called Primes, every of which contained in length 19•• Inches; again, every of those Primes was sub-divided into 10 other equall parts called Seconds, so that every of these Seconds contained in length 1 49/50 Inch, so that the whole Pole, Perch, Unite, or Commencement (as he calleth it) was divided into 130 equall parts or Links, called Seconds.

The Chain (or one Pole thereof) being thus divided, at the end of every 50 Links or halfe Pole, let a large Curtain ring be fastned,

so shall you have in a whole Chain of two Perches long, three of these Rings, the middlemost being the division of the two Poles. Then at the end of every Prime, that is, at the end of every ten Links, let a smaller Curtain Ring be fastened.

By this distinction of Rings, the Chain is divided into these three denominations, Unites, Primes, and Seconds, whose Characters are these, ◯ · ·, so that if you would expresse 40 Unites, 8 Primes, and 7 Seconds, they are thus to be written, 408̇7̇, by which you may perceive that those Figures which have no pricks over them are Unites or Intigers, and the figure under the first point Primes, and under the next Seconds: so also, three Unites, seven Primes, and two Seconds, will stand thus, 37̇2̇.

Besides these divisions, Master Rathborn for his own use, sewed at the end of every two Primes and a halfe (which is a quarter of a Pole) a small red cloth, and at every seven Primes and a halfe (being three quarters of a Pole) the like of yellow, or other discernable colour, which much helped him in the ready reckoning of the several Rings upon the Chain, remembring this Rule: That if it be the next Ring short of the Red, it is two Primes, if the next over three, if the next short of the yellow, seven Primes; if the next over eight; if the next short of the great halfe Ring it is four, the next over six: and if the next short of the middle great Ring, it is nine, and if the next over one.

¶ But here is to be noted, that if you use this distinction by co∣lours, you must alwayes work with one end of the Chain from you.

This Chain being thus divided and marked, you have every whole Pole equall to ten Primes, or 100 Seconds: every three quarters of a Pole, equall to seven Primes and a halfe, or 75 Seconds: every halfe Pole equall to five Primes, or 50 Seconds: and lastly, every quarter of a Pole equall to two Primes and a halfe, or 25 Seconds.

And here is to be noted, that in the ordinary use of this Chain, for measuring and platting, you need take notice only of Unites and Primes, which is exact enough for ordinary use, but in case that se∣paration or division of Lands into severall parts, you may make use of Seconds.