Now fill in the intervening spaces with headers, and one course of the brickwork will be complete. The next course of bricks is formed in exactly the same manner, by taking the bonding diagram and turning it over on the axis OP, and viewing it through the back of the paper on which it is printed. It would be well for the novice to draw a number of plans of alternate courses of brickwork by means of his diagram, and in a very short time he will find that he is able to draw such plans of brick wall in English bond without its aid. Fig. 83 shows alternate courses of bricks in right-angle junctions of walls of various thicknesses, to which the reader may compare his own plans obtained by the application of the diagram. It should be noticed that, where walls of equal thickness meet at right angles, it is only necessary to make the plan of one course; for in order to obtain the course above and below it is only necessary to make a tracing of any course and turn it over and view it through the back of the tracing paper, and if it is desired to test the bonding the traced course should be laid over the plan of the course from which it was traced.

A.External facings for walls of any thickness .

B.Internal facings for walls of epwol or unequal thickness and of on even. number of half bricks in. thickness.

C.Internal facings for walla of equal or unequal thickness and of on odd number of half bricks in. thickness .

D. Infernal facings for junction of a wall of on odd number of half bricks with awoll of an even, number of half bricks.

Fig. 84.

Of course it is possible to bond walls in a different manner to that shown in Fig. 83, and yet keep the facings the same. The usual difference met with in practice is the position of the queen-closers, a very common arrangement being that shown in Fig. 86. The objection to this arrangement is that continuous vertical joints are produced as shown by the blackened joints, and these considerably weaken the angle, whereas in the method shown in Fig. 83 vertical joints are almost entirely avoided at the angles. Small continuous vertical joints also occur in English bond at the stopped ends of walls, the continuous vertical joint coinciding with the joints in the closer. Both these defects are small enough to be inconsiderable.

Fig. 85.

## Plain Jambs

The vertical sides of openings in walls are called jambs, and they are formed in precisely the same manner as stopped ends, as shown in Fig. 83.

## Rebated (Or Rabbeted) Jambs

Jambs formed in two planes, one recessed behind the other, as in Fig. 87, are termed rebated jambs. The recessed jamb is sometimes called the internal jamb, while in walls in English bond is shown in Fig. 87. The internal jambs are usually recessed by a distance equal to some multiple of a quarter of the length of a brick.

Fig. 86.

9"wall

14'wall.

18 "wall.

22 1/2" wall.

Fig. 87. 27" wall.

the projecting jamb is called the external jamb, or Reveal.

The method of bonding the bricks in rebated jambs

9 "wall

14' wall.

18 wall