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RULE.

Multiply the fquare of of the girt by twice the length, and

the product is the content very near the truth *.

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Ex. 2. Required the content when the girt is 4 feet 2 inches, and the length 15 feet.

Ex.

the length 20 feet 6 inches?

Anf. 20 feet to inches.

3. What is the folidity, when the girt is 55 inches, and Anf. 34 feet 5 inch. 5 pts. Ex. 4. Required the folidity of a tree whofe girt is 6 feet 8 inches, and length 16 feet 4 inches.

Anf. 58 feet o inch. 10 pts. 8". Ex. 5. Required the folidity of a tree, the circumference being 30 inches, and the length 6 feet. Anf. 3 feet 3 inches. Ex. 6. Required the content of a tree whofe girt is 35 inches, and length 17 feet 8 inches.

Ex.

7.

Anf. 12 feet o inches 3 pts. 4". The girt is 90 inches, and the length 19 feet, required the folidity. Anf. 85 feet 6 inches. Ex. 8. How many folid feet are in a tree whofe girt is 95 inches, and length 25 feet? Anf. 125 feet 4 inches 2 pts. 3 A 2

By this rule these 9 examples are computed.

Ex.

Ex. 9. How many folid feet are in a tree 5 feet 5 inches girt, and 20 feet long? Anf. 46 feet 11 inches 4 pts.

TAPERING-TIMBER.

Tapering-timber is that which is thicker and broader at the one end than at the other.

When the tree tapers regularly, the dimensions may be ta ken at the middle for the mean dimensions; or they may be taken at both the ends, and half their fum will be the mean di menfions.

If the tree be very irregular, the dimenfions ought to be taken at feveral equidiftant places, and their fum divided: Or the tree may be divided into a certain number of lengths, the content of each part found feparately, and their fum will give the content of the whole.

The mean girt of round tapering trees is found in the fame manner. When trees have their bark on, it is customary to make an allowance, by deducting fo much from the girt as is judged fufficient to reduce it to fuch girt as it would have without the bark. In cak, the allowance is generally or 's of the girt; but in elm, afh, beech, &c. the bark not being fo thick, the deduction ought to be less.

EXAMPLE I.

A tapering-tree, whose length is 24 feet, the girt at the greater end being 7 feet, and at the lefs 1 foot; it is required to find its content according to the true method, alfo in the common way.

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A tree is girt in 6 different places, as follows:-In the first place, 9 feet; in the second, 6 feet 8 inches; in the third, 5 feet; in the fourth, 4 feet 9 inches; in the fifth, 4 feet 2 inches; and in the fixth, 3 feet 5 inches-required its folidity, its length being 12 feet.

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3.00 Anf. 30 feet 3 inches.

MASON

MASON-WORK.

To Mafonry belongs all forts of ftone-work; paving and causewaying are measured by the square yard.

Digging for foundations or vaults is estimated by the folid yard.

Slabs, chimney-pieces, &c. by the square foot.

Stones for hewn-work, marble blocks, columns, &c. by the folid foot; but marble-facings by the fuperficial foot, two inches being the ftandard thickness.

Hewn-work is generally measured by the fuperficial foot. The dimenfions are taken by a measuring-line, which is bent into all the hollows, and over the projections, in order to afcertain the extent of furface which has been shaped by the tool.

Ruble-work is estimated by the rood of 36 fquare yards; the ftandard thickness is 2 feet; and walls of any other thickness must be reduced to that standard.

The value of materials is charged by the folid measure, and of workmanship by the fuperficial measure *.

Circular work, arches, &c. are estimated double measure. Deductions for all vacancies, fuch as doors, windows, &c. are made with regard to materials, but none with regard to workmanship.

Different

When the thickness is unequal in different parts, it must be reduced to the standard of 2 feet, by making proper allowances on fuch parts as are thicker or thinner than others. For example, if the gable of a houfe is three feet thick, find the fuperficies, and to this fuperficies add one half of the fame.

Different methods are used in different places for taking the dimensions of a house; and indeed of these there is such a variety, that scarcely any general rule can be given. A measurer, therefore, before he proceeds to measure a house, ought to inform himself as to the nature of the agreement, the customs of the place with regard to the method of taking dimenfions, and of making allowances.

It is, however, a pretty general cuftom to add one half the thickness to the height of the fide walls, as an allowance for the extraordinary trouble of levelling, and a foot for every belt. This allowance is given at the ftated rate.

A gable-end, where there are no vents, may be confidered a triangle, and measured accordingly; but when there are vents, it is a trapezoid, and ought to be computed by the rule for its proper form.

Chimney stalks are measured by multiplying one-half the girt by the height.

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EXAMPLE. I.

Required the folid content of a wall whose length is 53 inches, its height being 12 feet, and thickness 3 feet.

F. In. 53 8

feet

12 6

644 O
26 10

670 10

3 0

2)2012 6

9)3018 9

36)335 3

9 11 3 9

1006 3 Anf. 9 roods 11 yards 3 feet 9 inches.

3018 9 ftandard,

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