Colour Coat.—1 of colour to 1½ of old Portland, to be laid about 1/8 inch in thickness. Specially prepared distemper colours should be used, and amongst such may be mentioned golden ochre, Turkey red, Indian red, manganese black, lime blue, and umber.
Final Surface Coat.—Aberthaw lime and selenitic cement, both sifted through a fine sieve—the proportions of the gauge depend upon the heat of the lime: or, Parian cement sifted as above—air-slaked for 24 hours, and gauged with water coloured with ochre, so as to give a creamy tone when the plaster dries out: or, 3 of selenitic cement to 2 of silver sand, both sifted as above—this may be used for out-door work.
Individual taste and experience must decide as to the thickness of the final coat, but if laid between 1/8 and 1/12 inch, and the lines cut with slanting edges, a side light gives emphasis to the finished result, making the outlines tell alternately as they take the light or cast a shadow. Plasterers' small tools of various kinds and knife-blades fixed in tool handles will be found suited to the simple craft of cutting and clearing off the final surface coat; but as to this a craftsman finds his own tools by experience, and indeed by the same acquired perception must be interpreted all the foregoing directions, and specially that ambiguous word, dear to the writers of recipes,—Sufficient.
Thus far method. Now, as to special aptitudes and limitations. Sgraffito work may claim a special aptitude for design whose centre of aim is line. It has no beauty of material like glass, no mystery of surface like mosaic, no pre-eminence of subtly-woven tone and colour like tapestry; yet it gives freer play to line than any of these mentioned fields of design, and a cartoon for sgraffito can be executed in facsimile, undeviated by warp and woof, and unchecked by angular tesseræ or lead lines. True, hardness of design may easily result from this aptitude, indeed is to a certain extent inherent to the method under examination, but in overcoming this danger and in making the most of this aptitude is the artist discovered.
Sgraffito from its very nature "asserts the wall"; that is, preserves the solid appearance of the building which it is intended to decorate. The decoration is in the wall rather than on the wall. It seems to be organic. The inner surface of the actual wall changes colour in puzzling but orderly sequence, as the upper surface passes into expressive lines and spaces, delivers its simple message, and then relapses into silence; but whether incised with intricate design, or left in plain relieving spaces, the wall receives no further treatment, the marks of float, trowel, and scraper remain, and combine to make a natural surface.
It compels the work to be executed in situ. The studio must be exchanged for the scaffold, and the result should justify the inconvenience. However carefully the scheme of decoration may be designed, slight yet important modifications and readjustments will probably be found necessary in the transfer from cartoon to wall; and though the ascent of the scaffold may seem an indignity to those who prefer to suffer vicariously in the execution of their works, and though we of the nineteenth know, as Cennini of the fifteenth century knew, "that painting pictures is the proper employment of a gentleman, and with velvet on his back he may paint what he pleases," still the fact remains, that if decoration is to attain that inevitable fitness for its place which is the fulfilment of design, this "proper employment of a gentleman" must be postponed, and velvet exchanged for blouse.
It compels a quick, sure manner of work; and this quickness of execution, due to the setting nature of the final coat, and to the consequent necessity of working against time, gives an appearance of strenuous ease to the firm incisions and spaces by which the design is expressed, and a living energy of line to the whole. Again, the setting nature of the colour coat suggests, and naturally lends itself to, an occasional addition in the shape of mosaic to the means at disposal, and a little glitter here and there will be found to go a long way in giving points of emphasis and play to large surfaces.
It compels the artist to adopt a limited colour scheme—a limitation, and yet one which may almost be welcomed as an aptitude, for of colours in decorative work multiplication may be said to be a vexation.
Finally, the limitations of sgraffito as a method of expression are the same as those of all incised or line work. By it you can express ideas and suggest life, but you cannot realise,—cannot imitate the natural objects on which your graphic language is founded. The means at disposal are too scanty. Item: white lines and spaces relieved against and slightly raised on a coloured ground; coloured lines and spaces slightly sunk on a white surface; intricacy relieved by simplicity of line, and again either relieved by plain spaces of coloured ground or white surface. Indeed they are simple means. Yet line still remains the readiest manner of graphic expression; and if in the strength of limitation our past masters of the arts and crafts have had power to "free, arouse, dilate" by their simple record of hand and soul, we also should be able to bring forth new achievement from old method, and to suggest the life and express the ideas which sway the latter years of our own century.