216 THE STONES OF VENICE CONSTRUCTION

§ 9. Farther, and finally. In proportion to the height and size of the building, and therefore to the size of its doors, will be the thickness of its walls, especially at the foundation, that is to say, beside the doors; and also in proportion to the numbers of a crowd will be the unruliness and pressure of it. Hence, partly in necessity and partly in prudence, the splaying or chamfering of the jamb of the larger door will be deepened, and, if possible, made at a larger angle for the large door than for the small one; so that the large door will always be encompassed by a visible breadth of jamb proportioned to its own magnitude. The decorative value of this feature we shall see hereafter.¹

§ 10. The second kind of apertures we have to examine are those of windows.

Window apertures are mainly of two kinds; those for outlook, and those for inlet of light, many being for both purposes, and either purpose, or both, combined in military architecture with those of offence and defence. But all window apertures, as compared with door apertures, have almost infinite license of form and size; they may be of any shape, from the slit or cross slit to the circle;* of any size, from the loophole of the castle to the pillars of light of the cathedral apse. Yet, according to their place and purpose, one or two laws of fitness hold respecting them, which let us examine in the two classes of windows successively, but without reference to military architecture, which here, as before, we may dismiss as a subject of separate science; only noticing that windows, like all other features, are always delightful, if not beautiful, when their position and shape have indeed been thus necessarily determined, and that many of their most picturesque forms have resulted

* The arch heading is indeed the best where there is much incumbent weight, but a window frequently has very little weight above it, especially when placed high, and the arched form loses light in a low room: therefore the square-headed window is admissible where the square-headed door is not.

¹ [See Stones of Venice, vol. iii. Appendix 10.]

[Version 0.04: March 2008]