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8 inches the breadth of the plain work in the cill according to the above dimensions,-then

8 2 8 Plain work.

622 Sunk work.

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Cornices are measured by girthing round the moulded parts, that is, the whole of the vertical and under parts, called moulded work :-for example, suppose a cornice project one foot, girth two feet, and is 40 feet in length, then the dimensions will be entered as under,

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All the vertical joints must be added to the above.

Cylindrical work is measured in the girth; and the surface is calculated to be equivalent to plain work twice taken.

For example, suppose it be required to measure the plain work or a cylinder, 10 feet long, and 5 feet in circumference, the dimensions would then be entered

10 0 500 Sup'. plain work, double measure.

5 0

Paving-slabs and chimney-pieces are found by superficia measure, as also are stones under two inches thick.

The manner in which the dimensions of a house are taken, vary according to the place and the nature of the agreement.

In Scotland, and most parts of England, if the builder engages only for workmanship, the dimensions are taken round the outside of the house for the length, and the height is taken for the width, and the two multiplied

together gives the superficial contents. This, however, applies only when the wall is of the same thickness all the way up; and when not, as many separate heights are taken as there are thicknesses. This mode of measuring gives it something more than the truth, by the addition of the four quoins, which are pillars of two feet square; but this is not more than considered sufficient to compensate the workmen for the extra labour in plumbing the quoins.

If there be a plinth, string, course-cornice, or blocking course, the height is taken from the bottom of the plinth to the top of the blocking course, including the thickness of the same; that is, the measurer takes a line or tape and be gins, we will suppose, at the plinth, then stretching the line to the top, bends it into the offset, or weathering, and, keeping the corner tight at the internal angle, stretches the line vertically upon the face of the wall, from the internal angle to the internal angle of the string; then girths round the string to the internal angle at the top of the string, and keeping the line tight at the upper internal angle, stretches it to meet the cornice; he then bends it round all the mouldings to the internal angle of the blocking course, from which he stretches the string up to the blocking course, to the farther extremity of the breadth of the top of the same; so that the extent of the line is the same as the vertical section stretched out this dimension is accounted the height of the building.

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With respect to the length, when there are any pilasters, breaks, or recesses, the girth of the whole is taken at the length. This method is, perhaps, the most absurd of any admitted in the art of measuring; since this addition in height and length, is not sufficient to compensate for the value of the workmanship on the ornamental parts.

The value of a rood of workmanship must be first obtained by estimation, that is, by finding the cost of each kind of work, such as plinth, strings, cornices, and architraves, &c. and adding to them the plain ashlar work, and the value of the materials, the amount of which, divided by the number of roods contained in the whole, give the mean price of a single rood. When the apertures or openings in a building are small, it is not customary to make deductions either for the materials or workmanship which are there deficient, as the trouble of plumbing and returning the quoins, is considered equivalent to the deficiency of materials occasioned by such aperture.

Elsam's Gentleman's and Builder's Assistant, gives the following information on the practice of measuring rough stone work.

To find the number of perches contained in a piece of rough stone-work.

If the wall be at the standard thickness, that is, 12 inches high, 18 inches thick, and 21 feet long, divide the area by 21, and the quotient, if any, will be the answer in perches, and the remainder, if any, is feet. If the wall be more or less than 18 inches thick, multiply the area of the wall by the number of inches in thickness, which product, divided by 18, and that quotient by 21, will give the perches contained.

Example. A piece of stone-work is 40 feet long, 20 feet high, and inches thick, how many perches are contained in it?

40 length.
20 height.

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The method last described, of finding the value of mason's work, is usually adopted, the perch being the standard of the country; but the most expeditious way of ascertaining the value, is to cube the contents of the wall, and to charge the work at per foot. To ascertain the value of common stone-work, a calculation should be made of the prime cost of all the component parts, consisting of the stones in the quarry, the expense of quarrying, land-carriage to the place where it is to be used, with the extra trouble and consequent expense in carrying the stone one, two, three, or more stories higher. Also the price of the lime when delivered, together with the extra expense of wages to workmen, if in the country; all these circumstances must be taken into consideration in finding the value of a perch of common stonework, the expense of which will be found to vary according to

local circumstances, in degrees scarcely credible; wherefore a definite price cannot, with propriety, be fixed.

BRICKLAYING

In building upon an inclined plane, or rising ground, the foundation must be made to rise in a series of level steps, according to the general line of the ground, to insure a firm bed for the courses, and prevent them from sliding; for if this mode be not adopted, the moisture in the foundations in wet weather, will induce the inclined parts to descend, to the manifest danger of fracturing the walls and destroying the building.

In walling, in dry weather, when the work is required to be firm, the best mortar must be used; and the bricks must be wetted, or dipped in water, as they are laid, to cause them to adhere to the mortar, which they would not do if laid dry; for the dry sandy nature of the brick absorbs the moisture of the mortar and prevents adhesion.

In carrying up the wall, not more than four or five feet of any part should be built at a time; for, as all walls shrink immediately after building, the part which is first carried up will settle before the adjacent part is carried up to it, and, consequently, the shrinking of the latter will cause the two parts to separate; therefore, no part of a wall should be carried higher than one scaffold, without having its contingent parts added to it. In carrying up any particular part, the ends should be regularly sloped off, to receive the bond of the adjoining parts on the right and left.

There are two descriptions of bonds; English bond, and › Flemish bond. In the English bond, a row of bricks is laid lengthwise on the length of the wall, and is crossed by another row, which has its length in the breadth of the wall, and so on alternately. Those courses in which the lengths of the bricks are disposed through the length of the wall, are termed stretching courses, and the bricks stretchers: and those courses in which the bricks run in the thickness of the lengths of the walls, heading courses, and the bricks headers.

The other description of bond, called Flemish bond, consists in placing a header and a stretcher alternately in the same course. The latter is deemed the neatest, and most elegant; but, in the execution is attended with great inconvenience, and, in most cases, does not unite the parts of a

wall with the same degree of firmness as the English bond. In general, it may be observed, that, whatever advantages are gained by the English bond in tying a wall together in its thickness, they are lost in the longitudinal bond; and vice-versa. To remove this inconvenience, in thick walls, some builders place the bricks in the cone at an angle of forty-five degrees, parallel to each other, throughout the length of every course, but reversed in the alternate courses; so that the bricks cross each other at right an gles. But even here, though the bricks in the cone have sufficient bond, the sides are very imperfectly tied, on account of the triangular interstices formed by the oblique direction of the internal bricks against the flat edges of those in the outside.

Concerning the English bond, it may be observed, that, as the longitudinal extent of a brick is nine inches, and its breadth four and a half, to prevent two vertical joints from running over each other at the end of the first stretcher from the corner, it is usual, after placing the return corner stretcher, which occupies half of the length of this stretcher, and becomes a header in the face, as the stretcher is b.low, to place a quarter brick on the side, so that the two together extend six inches and three-quarters, being a lap of two inches and a half for the next header. The bat thus introduced is called a closer. A similar effect may be ob tained by introducing a three-quarter bat at the corner of the stretching course, so that the corner header being laid over it, a lap of two inches and a quarter will be left, at the end of the stretchers below, for the next header, which being laid on the joint below the stretchers, will coincide with its middle.

In the winter, it is very essential to keep the unfinished wall from the alternate effects of rain and frost; for if it is exposed, the rain will penetrate into the bricks and mortar, and, by being converted into ice, expand, and burst of crumble the materials in which it is contained.

The decay of buildings, so commonly attributed to the effects of time, is, in fact, attributable to this source; h as finished edifices have only a vertical surface, the action and counter-action of the rain and frost extend not so rapidly as in an unfinished wall, where the horizontal surface permits the rain and frost to have easy access into the body of the work. Great care, therefore, must be taken as soon as the frost or stormy weather sets in, to cover the un

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