The common Measure for Land is the Acre, which by Statute is appointed to contain 160 Square Perches; and it matters. not in what form the Acre lyes in, fo it contains juft 160 Square Perches: As a Parallelogram 10 Perches one way, and 16 another contains an Acre; fo does 8 one way, and 20 another, and 4 one way and 40 the other. If then, having one fide given in Perchs you would know how far you muft go on the Perpendicular to cut off an Acre, you muft divide 160 (the Number of Square Prches in an Acre) by the given fide, the Quotient is your D fire. As for Example, the given fide 20 Perches. Divide 160 by 20 the Quotient is 8, by this I know that 20 Perches one way, and 8 another,including a Right-Angle will be the two fides of an Acres the other two fides must be parallel to these.

And here I think it convenient to infert this neceffary Table, fhewing the Length and Breadth of an Acre in Perches, Feet and parts of a Foot: But if your given fide. had been in any other fort of Measure; as for inftance in Yards you muft then have feen how many Square Yards had been in an Acre, and that Sum you must have divided by the Number of your given Yards, the Quotient would have answered the Queftion,

13112

1411

17 9

8142
J 36

Example.

If 24 Yards be given for the Breadth, how many Yards fhall there be in Length of the Acres.

Fift, I find that an Acre contains 4840 Square Yards, which I divide by 24, the Quotient is 2011 for the Length of the Acre And thus knowing well how to take the Length and Breadth of an Acre, you may alfo by the fame way know how to lay down any Number of Acres together.

Reducing of one fort of Square measure to another, is done as before taught in Long meafure by Multiplication and Divifion. And because Mr Gunter's Chain is chiefly ufed by Surveyors, I fhall only inftance in that, and fhew you how to turn any Number of Chains and Links into Acres, Rods and Perches: Note, that a Rod is the fourth part of an Acre.

And firft mark well that 10 Square Chains make an Acre, that is, to fay, one Chain in Breadth and 10 in Length, or 2 in Breadth and in Length, is the Acre; as you may fee by this fmall Table.

Ch.

053

53333

50

Ch.

Links.

Parts Li.

Breadth of an Acre.

Length of an Acre.

1234 9

zico'
16666

14223

125

And thus well weighing that 10 Chains make one Acre, if any Number of Chains be given you to turn into Ac. you muft divide them by 10, and the Quotient will be the Number of Acres contained

in fo many Chains.

But this Divifion, is abbreviated by only cuting off the laft

Figure, as if 1590 Chains were given to turn into Acres, by cutting off the laft Fgure 159 0, there is left 159 Acres, which is alone as if you had divided 1590 by 10. But if Chains and Links be given you together to turn into Acres, Roots and Perches, firft from the given Sum cut off 3 Figures, which is 2 Figures for the Links, and one for the Chains, what's left fhall be Acres. And to know how many Roods and Perches are contained in the Figures cut off, Multiply them by 4 from the product, cutting off the 3 laft Figures, you will have the Roods: And then to know the Perches, multiply the Figurees cut off from the Roods by 40, from which product cutting off again 3 Figures, you have the Perches, and the Figures cut off are a Thousand parts of a Perch.

Example. 1599 Square Chains, and 55 Links, how many Acres, Roods and Perches.

Acres 1591 455

4

Anf. 159 Ac. 3-Roods, Roods 318 20.
32 Perches. 800

40

1000

Perches 321800 On the contrary, if to any Number of Acres given, you add a Cypher, they will be turned into Chains, thus 99 Acres are 990 Chains, .100 Acres 1000 Chains, ETC. the same as it you had multiplitd the Acres by 10 And if you would turn Square Chains into square Links, add four Cypher & to the end of the Chains, so will 990 Chains b: 9900000 Links, 1000 Chains

be 10000000 Links, all one as it you had multiplyed 990 by 10000, the Number of Square Links contained in one Chain.

And now, whereas in Cafting up the Content of a piece of Land mealured by Mr Guntcr's Chain, viz. Multiplying Chaina and Links by Chains and Links, the pro. duct will be Square Links; you must there. fore from that product cut off 5 Figures to find the Acres; which is the same as if you divided the product by 100000,the Num.

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