altogether.

Sec. VII. Farther. Since the chance, in the one case, of horizontal
dislocation, in the other, of irregular fissure, is much increased by
the composition of the shaft out of joints or small stones, a larger
bulk of shaft is required to carry the given weight; and, _caeteris
paribus_, jointed and cemented shafts must be thicker in proportion to
the weight they carry than those which are of one block.

We have here evidently natural causes of a very marked division in
schools of architecture: one group composed of buildings whose shafts
are either of a single stone or of few joints; the shafts, therefore,
being gracefully tapered, and reduced by successive experiments to the
narrowest possible diameter proportioned to the weight they carry: and
the other group embracing those buildings whose shafts are of many
joints or of small stones; shafts which are therefore not tapered, and
rather thick and ponderous in proportion to the weight they carry; the
latter school being evidently somewhat imperfect and inelegant as
compared with the former.

It may perhaps appear, also, that this arrangement of the materials in
cylindrical shafts at all would hardly have suggested itself to a people
who possessed no large blocks out of which to hew them; and that the
shaft built of many pieces is probably derived from, and imitative of
the shaft hewn from few or from one.

Sec. VIII. If, therefore, you take a good geological map of Europe, and
lay your finger upon the spots where volcanic influences supply either
travertin or marble in accessible and available masses, you will
probably mark the points where the types of the first school have been
originated and developed. If, in the next place, you will mark the
districts where broken and rugged basalt or whinstone, or slaty
sandstone, supply materials on easier terms indeed, but fragmentary and
unmanageable, you will probably distinguish some of the birthplaces of
the derivative and less graceful school. You will, in the first case,
lay your finger on Paestum, Agrigentum, and Athens; in the second, on
Durham and Lindisfarne.

The shafts of the great primal school are, indeed, in their first form,
as massy as those of the other, and the tendency of both is to continual
diminution of their diameters: but in the first school it is a true
diminution in the thickness of the independent pier; in the last, it is
an apparent diminution, obtained by giving it the appearance of a