INTERCOLUMNIATION (from Lat. inter, between, columns, column), in classical architecture, refers to the clear space between two columns of a peristylos, or system of roof supporting columns, though sometimes it means the distance measured at the lower parts of shafts, between their centres, and referred to in terms of diameter of a column at its base. A Roman architect and engineer, Vitruvius, a contemporary of Augustus, enumerates five varieties of intercolumniation, assigning by means of the foregoing scale of measurement, definite proportions to each. They are as follows: 1. Pycnostylos (Gr. immoc, '
umns in a space equal to eight diameters and a half. The central intercolumniation is equal to three diameters and a half, and the others on each side only half a diameter, so that coupled columns are introduced.
In the ruined remains of fine architecture which have survived down to the present time, ancient intercolumniation rarely if ever illus trates the Vitruvian dimensions, which there fore have, by some authorities, been regarded as arbitrary. He appears to have spoken only of Roman forms, or only of those of the Greek style, with which he became acquainted through such reports about Hellenic temples, as he had among his authorities. In the Doric examples, such as the Parthenon and the temple of Diana Propylica at Eleusis, the proportion is said to be one and one-quarter (1%) diameters. Tem ples of the Ionic and Corinthian order resemble each other. The proportions in these are, on the whole, greater; they average about two diameters. But it would be a mistake to over took in this connection the relative proportion of height to diameter in a column, and to disre gard the width of the peristyle. In one temple of the Ionic order, that of Apollo Smintheus, in Asia Minor, the peristyle is of double width, ' and the intercolumniation is just one and one half diameters. To the ancients, the eustylos was the most correct as well as the most beau tiful arrangement; and the author of
Archi tectura) preferred this proportion to that of any of the others, declaring it at one and the same time the strongest and the most convenient. Consult Vitruvius, (De Architectura' (trans. by Morgan, Prof. Morris H., as