Nearly all houses are built of bricks, as they are less expensive
than stone, and more durable than wood, besides being less liable to
be burnt. Walls of brick may be formed of any required thickness, and
as the length of a brick is twice its breadth, they admit of being so
laid that the wall shall not part in pieces, which would be the case
if laid as in fig. 1, as the seams of mortar run continuously through
the wall, which in bricklaying is always avoided, by different
methods. Formerly bricks were laid in what was called “English bond”
(fig. 2), but this is not now used, “Flemish bond” (fig. 3) having
superseded it. The mortar with which bricks are laid is made of
lime and sand, mixed with water to a convenient consistence; it sets
quickly, hardens with age, and resists the action of rain and time.
The ordinary mode of laying bricks is to stretch a line from end
to end of the course on which they are to be laid; the surface of
the under course is spread for a short distance with mortar, and the
bricks intended to form the outer surface of the wall are laid first,
in an exact line with the cord, the “plumb” (fig. 4) being frequently
used to ascertain if they are perpendicular. The “plumb” is a piece
of board with a notch at the centre of the top, and a hole, also in
the centre, near the bottom; a piece of cord is passed through the
notch, with a leaden ball attached, which swings in the hole as the
plumb is placed at the side of the wall. The ball of lead just falls
in the hole if the wall is upright, and in this way a wall may be
built to any height, exactly perpendicular. The corner of brickwork
where windows occur, is called the “arris,” and has to be made
upright both in front and at the side. When very thick walls are to
be made (as in railway cuttings), the outer surface and back of the
walls are laid in the usual way, the space between is filled with
a layer of bricks, and thin liquid mortar is poured on and scraped
about with a sort of hoe till the spaces between the bricks are all
filled up and the surface left level, when another course is laid
in the same manner. Fig. 5 is a trowel, or instrument used to take
up and spread out the mortar, and fig. 6 is the hod, in which the
labourer carries supplies of bricks or mortar to the spot where the
bricklayer is working.