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, so it contains just 160 Square Perches : As a Parallelogram 10 Perches one way, and 16 another contains an Acre, so 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 must go on the Perpendicular to cut off an Acre, you muft divide 160 (the Number of Squ.re Pirches in ar Acre) by the given side, the Q11ctient is your D fire. As for Example, the given side 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 sides of an Acre; the other two sides must be parallel to these.

And here I think it convenient to insert this neceffry Table, fhewing the Length and Breadth of an Acre in Purches, Feet and parts of a Foot : But if your given side had been in any other sort of Measure; as for inftance in Yards you must then have seen 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 Question,

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

First, I find that an Acre contains 4840 Square Yards, which I divide by 24, the Quotient is 201 for the Length of the Acre And thus knowing well how to take the Length and Breadth of an Acre, you may also by the same way know how to lay down any Number of Acres together.

Reducing of one sort of Square measure to another, is done as before taught in Long measure by Multiplication and Division. And because Mr Gunter's Chain is chiefly used by Surveyors, I mall only inftance in that, and Drew you how to turn any Num. ber of Chains and Loks into Acres, Rods and Perches : Note, that a Rod is the fourth part of an Acre.

And first mark well that 10 Square Chains make an Acre, that is,' to say, one Chain in Breadth and io in Longih, or 2 in Breadth and Ŝ in Length, is the Acre; as you may fee by this small Table.

Ch.
Ch.
Links.
Parts Li. m

o Length of an Acre.

monin Breadth ot an Acre.

3150

2

125

And thus well weighing that 10 Chains make one Acre, if any

Number of Chains begi5133133 ven you to turn into Ac.

you muft divide thein

by 10, and the Quozico

tient will be the Nim116666

ber of Acres contained 1 42 23

in fo many Chains.

But this Division, is III abbreyiated by

on

ly cu ting off the last Figure, as if 1590 Chains were given to turn into Acres, by cutting off the last F:gure 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 tcgether 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 shall be Acres. And to know how many Roods and Parches are contained in the Figures cut off, Multi: ply them by 4 from the product, cutting off the 3 last 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 che 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.

bes