to start with the section, and from this to draw the plan and elevation. According to the rule, it is evident that the footings with one course of the given wall will consist of four courses, viz. 3, 21, 2, and 1 bricks. Draw (Fig. 11) centre and base lines AB and CD; upon the centre line mark up the four 3" courses 1, 2, 3, 4; upon the base-line measure off to the right and left 13", that is, half the width of the bottom course. Beyond this again on each side, for the sake of construction, allow a distance of 21′′, naming these points E and F. Through point 4 draw the top of the fourth course 63" on each side of the centre line; from each extremity of this line, to points E and F, draw faint raking lines; proceed through points 1, 2, 3, to draw other horizontal lines, terminating on each side at the raking lines. From the meeting points of the lines 1, 2, 3, 4 with the raking lines, drop perpendiculars to the lines below. Each offset will then be found to be 21". Now fill in each course with 9′′ stretchers, taking care that whenever a 4" header is necessary, it shall, when possible, be placed upon the inside of each course. Clean out the raking lines, and draw in the concrete as already described.

From the section, the plan (Fig. 12) may then be easily drawn below, and the elevation at the side,

as in Fig. 13, taking care that stretchers upon section appear as headers upon plan and elevation, and vice versa, and that the courses break joint by 21".

Fig. 14 is the section of footings

FIG. 14.

for a 2-brick wall, showing the bottom course doubled. The elevation and plan may be taken from it, as in Figs. 11 and 12.

BONDING.

Bond in brickwork means a tie or link. It is an arrangement having for its object the massing or building of bricks in such a manner as to make them, when so placed or built, act in concert together as a whole. For this purpose no vertical joint of one course should be less than a quarter of a brick from the vertical joint above or below, so that a sharp instrument inserted between two bricks and thrust downward should not be able to penetrate more than the thickness of a brick and a bed joint. This applies

not only to face bond, but internal bonding as well. This equalizes the strength of the bearing surface, and transmits the weight downward from one course to another. When bricks are so placed or built together they are termed walls.

The following are the principal kinds of bond, in their order of importance :

English bond, by far the strongest, and, in the opinion of many,

the best in appearance, consists of alternate courses of headers and stretchers (Fig. 15).

Flemish (double): alternate header and stretcher upon the same course and both sides of the wall (Fig. 16).

Flemish (single): Flemish bond outside with English backing.

Sussex or garden wall: three stretchers and a header alternately upon the same course.

FIG. 19.

Used principally to obtain fair face on both sides of a 9" wall (Fig. 17).

Stretching: stretchers upon

each course, for 44" walls (Fig. 18). Heading: headers only upon each course for circular corners (Fig. 19).

Diagonal and herring-bone: as lacing or strengthening courses in thick walls, and also for flooring (Figs. 20 and 21).

Rules for English Bond.-Whenever, in the thickness of a wall, there is an odd half-brick-e.g. 13 brick, 2 bricks-then, while

laying a heading course on one face, a stretching course should be laid upon the other, the remaining space being filled in with headers laid at right angles with the face-line. In the case of

B

A

FIG. 20.

FIG. 21.

quoins, etc., upon the internal angle, the stretcher should quarterbond with and project 21" from the heading course which is at right or any other angle to it.

When a wall is an even multiple of a brick in thickness-e.g. 2 bricks, 3 bricks, etc.—then, while a heading course is laid upon one face, a heading course will be laid upon the other; the same applying to the stretching course,

the quarter-bonding upon the internal angle being done by means of the header.

A

B

Transverse joints should be unbroken. There can be no excuse whatever for broken transverse joints, the weakness of which is shown in Figs. 22 and 23. Here it will be seen that a good face bond is obtained, but that in the 41" between A and B in the last diagram, the headers are joint upon joint, the strength being diminished almost to that of three 4" walls built against each other. This error is often incurred through quarterbonding, in walls having the odd half-brick in their thickness, upon the internal angle with a header.

FIGS. 22 and 23.

The centre of a header of one course should fall upon the centre of a stretcher in the course above and below.

The closer should always be next the quoin header.

It is only by understanding thoroughly and properly applying

these rules that correct bonding will be arrived at. That which appears to make brick bonding so difficult is want of system. The following is a systematic method to be adopted in drawing plans of alternate courses at the angle of a brick wall built in English bond:

The 1-brick wall (Figs. 24 and 25) will serve as an illustration. Draw the perpendicular lines AB and DE under one

A

B
DR

G

X

/H

another, and in the same straight line; from B and E draw the horizontals BC and EF. With the angle of 45° from B and E, draw faint mitre-lines BX and EH; set off from B towards C in the point the thickness of the wall, 1 brick; now with the distance BI draw lines parallel to AB and DE above, but termiC nating at the mitre-lines. From where these lines meet the mitres, draw horizontal lines beyond BI, but parallel to BC and EF; draw broken lines at the end of each block, and the outline diagrams will be finished. Clean out the mitre-lines. Take it for granted that the quoin header points in the direction of the arrow (Fig. 24); then, measuring out from the inner angle and F along the line parallel to BC, take a distance of 21", and drop a line from G, meeting with and at right angles to BC. This will be termed the governing or quarter-bonding line, and the necessity of fixing it cannot be too strongly insisted upon in every case, for upon this line depends the whole success of the bonding. As a heading course is required along BC, then a stretching course will appear along BA. Set off from B a distance of 9" along BA, and draw a line parallel to BC; then set off from B a distance of 4" along BC, and draw a line parallel to AB; and as the quoin header Q is already fixed, draw headers right and left of the governing line, filling in the remaining space next the quoin header with a closer,

E

FIGS. 24 and 25.

and taking care that each two headers are backed in immediately behind with a stretcher. Returning along BA, fill in with stretchers, backing in each with two headers.

The filling in of the bottom block will be a reversal of the top.

As a proof of the bonding, take a tracing of the first course,

and place it over the second, so that the outlines of the blocks coincide; then, if correct, all the joints seen will be 24" apart.

Figs. 26 and 27, and Figs. 28, 29, 30, 31, 32, and 33, are plans of alternate courses of 2, 2, 3, and 34-brick walls in the same