3. The reason for this result is that the eye, touching thus upon a greater number of points, set closer together, has a larger compass to cover with its range of vision. For if two columns, equally thick but one unfluted and the other fluted, are measured by drawing lines round them, one line touching the body of the columns in the hollows of the channels and on the edges of the flutes,
these surrounding lines, even though the columns are equally thick, will not be equal to each other, because it takes a line of greater length to compass the channels and the flutes. This being granted, it is not improper, in narrow quarters or where the space is enclosed, to use in a building columns of somewhat slender proportions, since we can help out by a duly proportionate number of flutings.
