the
brickwork. But this hides up the work, and so tends to promote bad work,
besides being often very unsightly.

Among other peculiarities of brickwork are the facilities for
introducing different colors and different textures of surface which it
presents, the ease with which openings and arches can be formed in it,
the possibility of executing ornament and even carving, and the ease
with which brickwork will combine with other building materials. It
cannot be well made use of for columns, though it may readily enough be
turned into piers or pilasters. It cannot, generally speaking, with
advantage be made use of for any large domes, though the inner dome of
St. Paul's and the intermediate cone are of brick, and stand well. But
it is an excellent material for vaulting arcades and all purposes
involving the turning of arches.

Brickwork must be said to be durable, but it requires care. If not of
the best, brickwork within the reach of the constant vibration caused by
the traffic on a railway seems to be in danger of being shaken to
pieces, judging from one or two instances that have come under my own
observation. The mortar, and even in some cases the bricks themselves,
will rapidly deteriorate if moisture be allowed to get into the heart of
a brick wall, and in exposed situations this is very apt to happen. Care
should always be taken to keep the pointing of external brickwork in
good order, and to maintain all copings and other projections intended
to bar the access of water coming down from above, and to stop the
overflowing of gutters and stack pipes, which soon soaks the wall
through and through.

Of course, if there is a failure of foundations, brickwork, as was
pointed out earlier, becomes affected at once. But if these be good, and
the materials used be sound ones, and if the other precautions just
recommended be taken, it will last strong and sturdy for an immense
length of time. In some cases, as for example in the Roman ruins, it has
stood for 1,500 years under every possible exposure and neglect, and
still shows something of a sturdy existence after all, though sadly
mutilated. If we now return to the question, What can be well done in
brickwork? no better answer can be given than to point to what has been
and is being done, especially in London and within our own reach and
observation.

Great engineering works, such as railway viaducts, the lining of railway
tunnels, the piers and even the arches of br