above become considerable, it may be necessary to support the cornice at
intervals with brackets; especially if it be required to project far, as
well as to carry weight; as, for instance, if there be a gallery on top
of the wall. This kind of bracket-cornice, deep or shallow, forms a
separate family, essentially connected with roofs and galleries; for if
there be no superincumbent weight, it is evidently absurd to put
brackets to a plain cornice or dripstone (though this is sometimes done
in carrying out a style); so that, as soon as we see a bracket put to a
cornice, it implies, or should imply, that there is a roof or gallery
above it. Hence this family of cornices I shall consider in connection
with roofing, calling them "roof cornices," while what we have hitherto
examined are proper "wall cornices." The roof cornice and wall cornice
are therefore treated in division D.

We are not, however, as yet nearly ready for our roof. We have only
obtained that which was to be the object of our first division (A); we
have got, that is to say, a general idea of a wall and of the three
essential parts of a wall; and we have next, it will be remembered, to
get an idea of a pier and the essential parts of a pier, which were to
be the subjects of our second division (B).

CHAPTER VII.

THE PIER BASE.

Sec. I. In Sec. III. of Chap. III., it was stated that when a wall had to
sustain an addition of vertical pressure, it was first fitted to sustain
it by some addition to its own thickness; but if the pressure became
very great, by being gathered up into PIERS.

I must first make the reader understand what I mean by a wall's being
gathered up. Take a piece of tolerably thick drawing-paper, or thin
Bristol board, five or six inches square. Set it on its edge on the
table, and put a small octavo book on the edge or top of it, and it will
bend instantly. Tear it into four strips all across, and roll up each
strip tightly. Set these rolls on end on the table, and they will carry
the small octavo perfectly well. Now the thickness or substance of the
paper employed to carry the weight is exactly the same as it was before,
only it is differently arranged, that is to say, "gathered up."[35] If
therefore a wall be gathered up like the Bristol board, it will bear
greater weight than it would if it remained a wall veil. The sticks into
which you gather it are called _Piers_. A pier is a coagulated wall.

Sec. II. Now you cannot