Mouldings which receive much rain, as copings, cills, tops of cornices etc., were very much more sloped than in Classic work, so as to throw off the wet more rapidly. The custom in modern Classic buildings, where the stone is not very hard, of putting lead on the upper surface, as well as the damage often sustained when this is neglected, show the reasonableness of this increased slope. They had to do with a more rainy climate, and generally with softer stone, than the ancients, and they designed their work accordingly. The under sides, again, of projecting mouldings, as string-courses, drip-stones, water-tables, cills, etc., were carefully designed so as to prevent the wet from running round them. Base mouldings round buildings were designed in such a manner as both really and apparently to give it a substantial footing, and at the same time to add greatly to its beauty; many of them are as noble combinations as could easily be conceived.[60] In short, it may be asserted, without fear of contradiction, that in no style of architecture has a system of moulding been generated so full of variety and so capable of suiting itself to every position; and not only to provide for the practical demands of each position, but to give to each just that kind of effect which it most demanded. Let us now proceed to consider the _window_. In the days of ancient Greece, and in the earlier days of Rome, windows were necessarily kept in a very undeveloped form, through the non-existence of window glass; so much so, that in Classic architecture the window seems a thing shunned as an unhappy necessity; and the imperfect manufacture and dearness of this material, no doubt, influenced, in a considerable degree, the architecture of the later Roman and the immediately succeeding periods. In churches and other vaulted buildings, another cause would lead to the use, during the last-named (_i.e._, the Romanesque) period, of as small windows as would just answer the purpose. The unaided thickness and the whole length of the wall being relied on for the abutment of the vaulting, it naturally followed that perforations were as much avoided as possible, as tending to reduce the abutting mass. Accordingly, as buttresses increased in projection, greater and greater openings in the curtain wall were ventured on, simply because there was strength sufficient to admit of them, till, when Pointed architecture received its full development, and the pressure of the vaults was entirely concentrated upon the buttresses, the whole intervening space might, if needful, be converted into windows. Simultaneously with this change, the increasing use of stained glass _necessitated_ a corresponding increase in the area of window opening, so that we have one development _facilitating_, and the other _rendering necessary_, the constant enlargement and multiplication of the windows.