e. This is best when the joint is what is called a
weather joint--i.e., one in which the joint slopes outward. Sloping it
inward is not good, as it lets in wet; finishing it with a hollow on the
face is often practiced, and is not bad. Bricklayers, however, most of
them prefer that the mortar joints should be raked out and pointed--that
is to say, an inch or an inch and a half of the mortar next the outer
face be scratched out and replaced with fresh mortar, and finished to a
line.

In cases where the brickwork is exposed to frost, this proceeding cannot
be avoided, because the frost damages the external mortar of the joints.
But the bricklayers prefer it at all seasons of the year, partly because
brickwork is more quickly done if joints are not struck at the time;
partly because they can, if they like, wash the whole surface of the
work with ocher, or other color, to improve the tint; and partly
because, whether the washing is done or not, it smartens up the
appearance of the work. The misfortune is that this pointing, instead of
being the edge of the same mortar that goes right through, is only the
edge of a narrow strip, and does not hold on to the old undisturbed
mortar, and so is far less sound, and far more liable to decay. There is
a system of improving the appearance of old, decayed work by raking out
and filling up the joint, and then making a narrow mortar joint in the
middle of this filling in, and projecting from the face. This is called
tuck pointing. It is very specious, but it is not sound work.

Brick arches are constantly being turned, and of many sorts. An arch
consists of a series of wedge shaped blocks, known as voussoirs,
arranged in a curve, and so locking one another together that unless the
abutments from which the arch springs give way, it will not only carry
itself, but sustain a heavy load. It is a constant practice to cut
bricks to this shape and build them into an arch, and these are
sometimes cut and rubbed; sometimes, when the work is rougher, they are
axed. But in order to save the labor of cutting, arches are sometimes
turned with the bricks left square, and the joints wedge shaped. In this
case the rings should be only half a brick each, so that the wedge need
not be so very much wider at back than at face, and they are set in
cement, as that material adheres so closely and sets so hard. Arches of
two or more half-brick rings in cement are good construction, and are
also used for culve