Some writers assert that, in Mediaeval times, the interiors of cathedrals were always painted.

Is that the fact?
Or, admitting that the statement is correct as to all Romanesque churches, is it equally so with regard to Gothic churches?
"For my part, I like to believe that the sanctuary of Chartres was never befooled with gaudiness, such as we have to endure at Saint Germain des Pres, in Paris, and Notre Dame la Grande at Poitiers.

In fact such colour can only be conceived of--if at all--as used in small chapels; why stain the walls of a cathedral with motley?
For this tattooing, so to speak, reduces the sense of space, brings down the roof, and makes the pillars clumsy; in short, it eliminates the mysterious soul of the nave, and destroys the sober majesty of the aisle with its feebly vulgar fret or guilloche, lozenges or crosses, scattered over the pillars and walls, in a paste of treacly yellow, endive-green, vinous purple, lava drab, brick red--a whole range of dull and dirty colours; to say nothing of the horror of a vault dotted with stars that look as if they had been cut out of gilt paper and stuck against a smalt background, a sky of washing-blue! "It is endurable--if it must be--in the Sainte-Chapelle, because it is very small, an oratory, a shrine; it might even be intelligible in that wonderful church at Brou, which is a boudoir; its vaulting and pendants are in polychrome and gold, and the ground has been paved with enamelled tiles, of which visible traces remain round the tombs.

This gaudiness of the roof and floor was in harmony with the filagree tracery of the walls, the heraldic glass, and the clear windows, the profusion of lace-like carving and coats of arms in the stone-work, blossoming with bunches of daisies mingling with labels, mottoes, monograms, Saint Francis' girdles and knots.

The colouring was in keeping with the alabaster retables, the black marble tombs, the pinnacled tabernacles with their crockets of curled and dentate foliage.