These have a variable surface, without reflections, and make not only a soft and impalpable colour effect, but, on account of their want of reflection, are good backgrounds for pictures.
In these papers the colour is produced by a mixture in the mass of paper pulp of atoms of varying tint, which are combined in the substance and make one general tint resulting from the mixture of several.

In canvases and textiles, which are a more expensive method of producing almost the same mixed effect, the minute points of brilliance of threads in light and darkness of threads in shadow, combine to produce softness of tone, impossible to pigment because it has but one plain surface, unrelieved by breaking up into light and shadow.
Variation, produced by minute differences, which affect each other and which the eye blends into a general tone, produce quality.

It is at the same time soft and brilliant, and is really a popular adaptation of the philosophy of impressionist painters, whose small dabs of pure colour placed in close juxtaposition and fused into one tone by the eye, give the purity and vibration of colour which distinguishes work of that school.
Some skilful painters can stipple one tone upon another so as to produce the same brilliant softness of effect, and when this can be done, oil-colour upon plaster is the best of all treatment for bedrooms since it fulfils all the sanitary and other conditions so necessary in sleeping-rooms.

The same effect may be produced if the walls are of rough instead of smooth plaster, so that the small inequalities of surface give light and shadow as in textiles; upon such surfaces a pleasant tint in flat colour is always good.

Painted burlaps and certain Japanese papers prepared with what may be called a textile or canvas surface give the same effect, and indeed quality of tint and tone is far more easily obtained in wall-coverings or applied materials than in paint, because in most wall-coverings there are variations of tint produced in the very substance of the material.
This matter of variation without contrast in wall-surface, is one of the most important in house decoration, and has led to the increased use of textiles in houses where artistic effects have been carefully studied and are considered of importance.
Of course wall-paper must continue to be the chief means of wall-covering, on account of its cheapness, and because it is the readiest means of sheathing a plaster surface; and a continuous demand for papers of good and nearly uniform colour, and the sort of inconspicuous design which fits them for modest interiors will have the effect of increasing the manufacture of desirable and artistic things.
In the meantime one should carefully avoid the violently coloured papers which are made only to sell; materials which catch the eye of the inexperienced and tempt them into the buying of things which are productive of lasting unrest.