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job. There are several arguments in the favour of fixing inside : the pipes are out of the way of frost and the different temperatures of the outside atmosphere; the warmth of the house rarefies the air inside the pipes, which causes a better up-current; and it saves damaging the house by cutting through the walls for the various branches. There is no reason, if the pipes are fixed inside, why they should be hidden; a good plan is to provide a chase plastered and finished in Parian cement, then to fix the pipes and leave them exposed; the chase and pipes may be painted to match the existing work."

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PART II

GAUGED WORK, ARCHES, ARCH

CUTTING, ETC.

GAUGED work consists in rubbing and cutting to any required shape specially made bricks, or “rubbers," as they are technically termed.

This class of work is usually done in what is called a cutting shed, provided with a bench about 2' 3" high and 2' 6" wide.

! FIG. 135.

FIG. 136.

The tools and appliances required are a rubbing stone (Park Spring, for preference), circular in shape, and 14" diameter; a bow saw fitted with twisted annealed wire No. 18 gauge, parallel file 16" long, small tin scribing saw, square, bevel, straight pieces of gas

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barrel for hollows in mouldings, etc., bedding slate to try the work for accuracy, straight-edges, compass, setting trowel, putty box (Fig. 135), boaster, club hammer, and scotch (the three latter for axed work), reducing boxes for thickness (Fig. 136) and for length (Fig. 137), moulding boxes (Fig. 138), boxes with radial sides for obtaining the wedge-shape voussoir according to the template

(Fig. 139), a setting-out board about 6' 0" X 5' 0", and lining paper 2'6" wide, etc.

The most elementary kind of gauged work is that which is known as plain

ashlar, consisting of heading Fig. 139.

and stretching courses for plain facing. The operations are as follows: First bed the brick, i.e. place the brick with the letter or hollow side on the rubbing stone; then, holding the brick with both hands, rub it upon the stone, giving it a circular motion from right to left, and trying it occasionally with a straight-edge till the bed of the brick has become a perfect plane.

Next, with the rubbed bed turned from the body, place the side or face of the brick upon the stone, and rub as before, at the same time endeavouring to make the side square with the bed, testing it by application of the square, stock to the side, and the blade to the bed of the brick. Then serve the head in the same way, making it square with both bed and face. After these operations are perfect, the brick has to be reduced to thickness; this is done by placing it on its bed in a reducing box (Fig. 136), the measurement of the inside depth of which is 32" under 3", sawing off the superfluous material and finishing with a file.

If for a stretcher, next place the brick face downwards in a 9" lengthening box (Fig. 137), making the square end to coincide with the front edge A of the box, and saw off to length, finishing with a file at the back edge B. The cut stretcher will be 9" less

1 11 32

" in length.

In preparing long headers, the bricks would have to be placed in the same box, face downwards, but the saw and file would be used along the top edge of the box, thus making the header 4.}" less 32" in width.

If for bat headers, then the squared end is placed downwards in the box, and saw and file used along the top edge again.

Arches.—These may be plain, axed, or gauged.

In plain or rough arches the bricks are not cut at all, the joints alone give the radiation, and the arch is usually made up of rings.

The Relieving Arch. The relieving or discharging arch (Fig. 140), as its name implies, is used for the purpose of relieving the weight from any portion of the building which is too weak to bear it, and discharging or transmitting it to piers, etc., specially prepared to receive the load. They are sometimes used in the face of buildings, when they are also treated as ornamental features.

The most frequent use for the relieving arch is inside the building, over door and window openings. The opening is first bridged by the lintel, which should rest not less than 4}" upon the jambs each side of the opening; next a brick core is built throughout the entire length of the lintel to serve as a turning piece for the arch; the curve being

ARCB obtained by means of a curved

Fig. 140. mould having the same rise it is intended to give the arch. This is applied to the face of the core; the bricks are marked, and then cut to shape. A skewback, which should radiate from the striking point, is built at each end of the lintel; and the arch, consisting of 43" brick rings, but starting with a stretcher at each end upon the skewback, is then turned over the core.

When a flat rise only is given, the brick core is done away with, and the curve is worked upon the lintel.

It must not be forgotten that the lintel is in length the exact span of the arch; that the object of the lintel is for the purpose of fixing the joinery; that the core acts only as a turning piece for the arch, and to fill up the space between this and the lintel; and that neither of them influences the strength of the discharging arch in any way. Should a fire occur, the lintel would burn and the core fall, but the arch ought to remain intact. The method of striking out the arch will be the same as that given for the segment.

When arranging the rings, those starting from the top and working downwards alternately should always have a key-brick; the other rings will key in with a joint. As already stated, in this as in all other rough arches, the bricks themselves are square, and the radiation is obtained by means of the joint. The mode of drawing the radial joint is as follows: Prick over the 3" courses, and fill in the face from the radial point R, as in the semi-arch (p. 50). Through the radial point, and parallel with the lintel, draw an indefinite line AB; make one of the courses or bricks of the arch parallel, by keeping the top equal to the bottom of the brick; produce the line which does this so that it cuts the line AB, in C, then C will be the point by means of which a line drawn from it through the soffit end of the face joint of each course will give the radial joint. This method must be followed each side of the arch.

The Invert Arch.—It often occurs that the principal loads in buildings, such as girders carrying the floors, etc., are concentrated upon certain points, as piers, for instance, which are usually strengthened to receive them. Should there be openings upon each or one side only of the pier, it is very evident that the weight of the pier and its load would be taken vertically downward to one part of the footings only, little able, perhaps, to bear it, To relieve the special part of some of the weight, by spreading A

it over a larger area of footings, invert arches are used, as in Fig. 141. Here some of the weight is taken from

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the pier A and its fellow, and transmitted by the invert arch to the footings in between them. It will be noticed that the lines from the radial point to the skewbacks form an angle of 45°, this being found to be the best angle to receive the weight.

Chimney breasts in basement stories are often treated in this way.

Egg-shaped Sewer (Fig. 142).—This sewer, as its name indicates, is shaped like an egg, with the smaller end downwards,

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