As a result, he is usually content to let color problems alone, for they are just another complication of his already too complicated life; or he refers them to some one whom he thinks ought to know—­a manufacturer’s designer—­and approves almost anything submitted.  Of course the ideal architect would have time for every problem, and solve it supremely well; but the real architect is all too human:  there are depressions on his cranium where bumps ought to be; moreover, he wants a little time left to energize in other directions than in the practice of his craft.  One of the functions of architecture is to reveal the inherent qualities and beauties of different materials, by their appropriate use and tasteful display.  An onyx staircase on the one hand, and a portland cement high altar on the other, alike violate this function of architecture; they transgress that beautiful necessity which decrees that precious materials should serve precious uses and common materials should serve utilitarian ends.  Now color is a precious thing, and its highest beauties can be brought out only by contrast with broad neutral tinted spaces.  The interior walls of a mediaeval cathedral never competed with its windows, and by the same token, a riot of polychromy all over the side of a building is not as effective, even from a chromatic point of view, as though it were confined, say, to an entrance and a frieze.  Gilbert’s witty phrase is applicable here: 

  “Where everybody’s somebody, nobody’s anybody.”

Let us build our walls, then, of stone, or brick, or stucco,—­for their flat surfaces and neutral tints conduce to that repose so essential to good architectural effect:  but let us not rest content with this, but grant to the eye the delight and contentment which it craves, by color and pattern placed at those points to which it is desirable to attract attention, for they serve the same aesthetic purpose as a tiara on the brow of beauty, or a ring on a delicate white hand.  But just as jewelry is best when it is most individual, so the ornament of a building should be in keeping with its general character and complexion.  A color scheme should not be chosen at random, but dictated by the prevailing tone and texture of the wall surfaces, with which it should harmonize as inevitably as the blossom of a bush with its prevailing tone of stems and foliage.  In a building this prevailing tone will inevitably be either cold or warm, and the color scheme just as inevitably should be either cold or warm; that is, there should be a preponderance of cold colors over warm, or vice versa.  Otherwise the eye will suffer just that order of uneasiness which comes from the contemplation of two equal masses, whereas it experiences satisfaction in proportionate unequals.

Nothing will take the place of an instinctive colour-sense, but even that needs the training of experience, if the field be new, and a few general principles of all but universal application will not be amiss.