From this dependence for its effect on the actual material used, it follows that the work of no period is more easily damaged than this by so-called "restoration." The introduction of only half a dozen pieces of crudely coloured modern glass is often enough to upset the whole harmony of the colour and to make the window irritating instead of restful to the eye. In France, indeed, so few windows of this period have been left unrestored that the period does not always get justice done it. I doubt if many people honestly get much pleasure from the effect of the windows of the Sainte Chapelle at Paris taken as a whole; but if you notice how much of the original glass is in South Kensington Museum you will understand the reason.
(3) _The Influence of Iron-Work._--The windows of this period consisted from the first, as we have seen, of separate leaded panels inserted into the openings of an iron lattice. This lattice was formed of iron bars of a =T= shaped section, the head of the =T= being outwards, and having staples at intervals on the inner rib, through which light iron bars were thrust and keyed with wedges, to hold the glass in its place.
In the absence of any tracery to assist in the support of the glass, this iron-work in large windows was of a massive character and could not be disregarded in the design. In figure work there were two possible ways of dealing with it: one was to make the figures so large as to be independent of it; and the other was to make the figures so small that a complete figure-subject could be included in one opening of the frame work.
Both these methods were used by the artists of the early period. Where the work is far from the eye, as in the clerestory windows, we usually find large single figures--far larger, often, than life--filling the whole window, like the big angel from Chartres on Plate X. and the smaller and older figure of Methuselah from Canterbury on Plate III. When, on the other hand, the work is near the eye, as in the aisle windows, they used the other method, filling each opening of the iron-work with a small subject-panel like that of Noah and the Dove in Plate IV., thus producing what is called the medallion window.
At first the lattice work consisted merely of upright and horizontal bars. These, it is true, sometimes, as in the twelfth century window at Poitiers in Plate II., were manipulated to fit the subject, but more usually the subject fitted the bars.