paper being laid uppermost, and over the face of the plan to be copied. Lay them, with the back of the old plan, on the glass; namely, that part which you intend to begin at to copy first; and by means of the light shining through the papers, you will very distinctly perceive every line of the plan through the clean paper. In this state then trace all the lines on the paper with a pencil. Having drawn that part which covers the glass, slide another part over the glass, and copy it in the same manner. Then another part. And so on, till the whole is copied. Then take them asunder, and trace all the pencil lines over with a fine pen and Indian ink, or with common ink. And thus you may copy the finest plan, without injuring it in the least.

OF ARTIFICERS' WORKS,

AND

TIMBER MEASURING.

Ì. OF THE CARPENTER'S OR SLIDING RULE.

THE Carpenter's or Sliding Rule, is an instrument mucli used in measuring of timber and artificers' works, both for taking the dimensions, and computing the contents.

The instrument consists of two equal pieces, each a foot in length, which are connected together by a folding joint. One side or face of the rule is divided into inches, and eighths, or half-quarters. On the same face also are several plane scales, divided into twelfth parts by diagonal lines; which are used in planning dimensions that are taken in feet and inches. The edge of the rule is commonly divided deeimally, or into tenths; namely, each foot into ten equal parts, and each of these into ten parts again: so that by means of this last scale, dimensions are taken in feet, tenths, and hundredths, and multiplied as common decimal numbers, which is the best way.

On the one part of the other face are four lines, marked A, B, C, D; the two middle ones в and c being on a slider, which runs in a groove made in the stock. The same numbers serve for both these two middle lines, the one being above the numbers, and the other below.

VOL. II.

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These

These four lines are logarithmic ones, and the three A, B, e, which are all equal to one another, are double lines, as they proceed twice over from 1 to 10. The other or lowest line, D, is a single one, proceeding from 4 to 40. It is also called the girt line, from its use in computing the contents of trees and timber; and on it are marked wG at 17∙15, and AG at 18-95, the wine and ale gage points, to make this instrument serve the pupose of a gaging rule.

On the other part of this face, there is a table of the value of a load, or 50 cubic feet of timber, at all prices, from 6 pence to 2 shillings a foot.

When 1 at the beginning of any line is accounted 1, then the 1 in the middle will be 10, and the 10 at the end 100; but when I at the beginning is counted 10, then the 1 in the middle is 100, and the 10 at the end 1000; and so on. And all the smaller divisions are altered proportionally.

II. ARTIFICERS' WORK.

ARTIFICERS compute the contents of their works by several different measures. As,

Glazing and masonry, by the foot; Painting, plastering, paving, &c, by the yard, of 9 square feet: Flooring, partitioning, roofing, tiling, &c, by the square of 100 square feet:

And brickwork, either by the yard of 9 square feet, or by the perch, or square rod or pole, containing 2724 square feet, or 30 square yards, being the square of the rod or pole of 16 feet or 54 yards long.

As this number 2724 is troublesome to divide by, the is often omitted in practice, and the content in feet divided only by the 272.

All works, whether superficial or solid, are computed by the rules proper to the figure of them, whether it be a triangle, or rectangle, a parallelopiped, or any other figure.

III. BRICKLAYERS' WORK.

BRICKWORK is estimated at the rate of a brick and a half thick. So that if a wall be more or less than this standard thickness, it must be reduced to it, as follows:

Multiply the superficial content of the wail by the number of half bricks in the thickness, and divide the product by 3.

The

The dimensions of a building may be taken by measuring half round on the outside and half round it on the inside; the sum of these two gives the compass of the wall, to be multiplied by the height, for the content of the materials.

Chimneys are commonly measured as if they were solid, deducting only the vacuity from the hearth to the mantle, on account of the trouble of them. All windows, doors, &c, are to be deducted out of the contents of the walls in which they are placed.

EXAMPLES.

EXAM. 1. How many yards and rods of standard brickwork are in a wall whose length or compass is 57 feet 3 inches, and height 24 feet 6 inches; the wall being 24 bricks or 5 half bricks thick ? Ans. 8 rods, 174 yards.

EXAM. 2. Required the content of a wall 62 feet 6 inches long, and 14 feet 8 inches high, and 24 bricks thick? Ans. 169-753 yards.

EXAM. 3. A triangular gable is raised 174 feet high, on an end wall whose length is 24 feet 9 inches, the thickness being 2 bricks: required the reduced content?

Ans. 32.08 yards.

EXAM. 4. The end wall of a house is 28 feet 10 inches long, and 55 feet 8 inches high, to the eaves; 20 feet high is 24 bricks thick, other 20 feet high is 2 bricks thick, and the remaining 15 feet 8 inches is 1 brick thick; above which is a triangular gable, of 1 brick thick, which rises 42 courses of bricks, of which every 4 courses make a foot. What is the whole content in standard measure? Ans. 253-626 yards.

IV. MASONS' WORK.

To Masonry belong all sorts of stone-work; and the measure made use of is a foot, either superficial or solid.

Walls, columns, blocks of stone or marble, &c, are measured by the cubic foot; and pavements, slabs, chimneypieces, &c, by the superficial or square foot.

Cubic or solid measure is used for the materials, and square measure for the workmanship.

In the solid measure, the true length, breadth, and thickness are taken and multiplied continually together. In the superficial, there must be taken the length and breadth of every part of the projection which is seen without the general upright face of the building.

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EXAMPLES

EXAMPLES.

EXAM. 1. Required the solid content of a wall, 53 feet 6 inches long, 12 feet 3 inches high, and 2 feet thick? Ans. 1310 feet. EXAM. 2. What is the solid content of a wall, the length being 24 feet 3 inches, height 10 feet 9 inches, and 2 feet thick? Ans. 521.375 feet. EXAM. 3. Required the value of a marble slab, at 8s. per foot; the length being 5 feet 7 inches, and breadth 1 foot 10 inches? Ans. 4. 1s. 101d.

EXAM. 4. In a chimney piece, suppose the

length of the mantle and slab, each 4 feet 6 inches

breadth of both together

V. CARPENTERS' AND JOINERS' WORK.

To this branch belongs all the wood-work of a house, such as flooring, partitioning, roofing, &c.

Large and plain articles are usually 'measured by the square foot or yard, &c; but enriched mouldings, and some other articles, are often estimated by running or lineal measure; and some things are rated by the piece.

In measuring of Joists, take the dimensions of one joist, and multiply its content by the number of them; considering that each end is let into the wall about of the thickness, as it ought to be.

Partitions are measured from wall to wall for one dimension, and from floor to floor, as far as they extend, for

the other.

The measure of Centering for Cellars is found by making a string pass over the surface of the arch for the breadth, and taking the length of the cellar for the length: but in groin centering, it is usual to allow double measure, on account of their extraordinary trouble.

In Roofing, the dimensions, as to length, breadth, and depth, are taken as in flooring joists, and the contents computed the same way.

In Floor-boarding, take the length of the room for one dimension, and the breadth for the other, to multiply together for the content.

For Stair-cases, take the breadth of all the steps, by making

a line ply close over them, from the top to the bottom, and multiply the length of this line by the length of a step, for the whole area. By the length of a step is meant the length of the front and the returns at the two ends; and by the breadth is to be understood the girts of its two outer surfaces, or the tread and riser.

For the Balustrade, take the whole length of the upper part of the hand-rail, and girt over its end till it meet the top of the newel-post, for the one dimension; and twice the length of the baluster on the landing, with the girt of the handrail, for the other dimension.

For Wainscoting, take the compass of the room for the one dimension; and the height from the floor to the ceiling, making the string ply close into all the mouldings, for the other.

For Doors, take the height and the breadth, to multiply them together for the area.-If the door be panneled on both sides, take double its measure for the workmanship; but if one side only be panneled, take the area and its half for the workmanship.-For the Surrounding Architrave, girt it about the uttermost part for its length; and measure over it, as far as it can be seen when the door is open, for the breadth.

Window-shutters, Bases, &c, are measured in like manner.

In measuring of Joiners' work, the string is made to ply close into all mouldings, and to every part of the work over which it passes.

EXAMPLES.

EXAM. 1. Required the content of a floor, 48 feet 6 inches long, and 24 feet 3 inches broad? Ans. 11 sq. 76 feet. EXAM. 2. A floor being 36 feet 3 inches long, and 16 feet 6 inches broad, how many squares are in it?

Ans. 5 sq. 98 feet. EXAM. 3. How many squares are there in 173 feet 10 inches in length, and 10 feet 7 inches height, of partitioning? Ans. 18.3973 squares.

EXAM. 4. What cost the roofing of a house at 10s. 6d. a square; the length within the walls being 52 feet 8 inches, and the breadth 30 feet 6 inches; reckoning the roof of the flat? Ans. 12/. 12s. Vląd.