OF SGRAFFITO WORK
The Italian words Graffiato, Sgraffiato, or Sgraffito, mean "Scratched,"
and scratched work is the oldest form of graphic expression and surface decoration used by man.
The term Sgraffito is, however, specially used to denote decoration scratched or incised upon plaster or potter"s clay while still soft, and for beauty of effect depends either solely upon lines thus incised according to design, with the resulting contrast of surfaces, or partly upon such lines and contrast, and partly upon an under-coat of colour revealed by the incisions; while, again, the means at disposal may be increased by varying the colours of the under-coat in accordance with the design.
Of the potter"s sgraffito I have no experience, but it is my present purpose briefly and practically to examine the method, special apt.i.tudes, and limitations of polychrome sgraffito as applied to the plasterer"s craft.
First, then, as to method. Given the wall intended to be treated: granted the completion of the scheme of decoration, the cartoons having been executed in several colours and the outlines firmly p.r.i.c.ked, and further, all things being ready for beginning work. Hack off any existing plaster from the wall: when bare, rake and sweep out the joints thoroughly: when clean, give the wall as much water as it will drink: lay the coa.r.s.e coat, leaving the face rough in order to make a good key for the next coat: when sufficiently set, fix your cartoon in its destined position with slate nails: pounce through the p.r.i.c.ked outlines: remove the cartoon: replace the nails in the register holes: mark in with a brush in white oil paint the s.p.a.ces for the different colours as shown in the cartoon, and pounced in outline on the coa.r.s.e coat, placing the letters B, R, Y, etc., as the case may be, in order to show the plasterer where to lay the different colours--Black, Red, Yellow, etc.: give the wall as much water as it will drink: lay the colour coat in accordance with the lettered s.p.a.ces on the coa.r.s.e coat, taking care not to displace the register nails, and leaving plenty of key for the final surface coat.
In laying the colour coat, calculate how much of the colour surface it may be advisable to get on the wall, as the same duration of time should be maintained throughout the work between the laying of the colour coat and the following on with the final surface coat--for this reason, if the colour coat sets hard before the final coat is laid, it will not be possible to sc.r.a.pe up the colour to its full strength wherever it may be revealed by incision of the design. When sufficiently set, _i.e._ in about 24 hours, follow on with the final surface coat, only laying as much as can be cut and cleaned up in a day: when this is sufficiently steady, fix up the cartoon in its registered position: pounce through the p.r.i.c.ked outlines: remove the cartoon and cut the design in the surface coat before it sets: then, if your register is correct, you will cut through to different colours according to the design, and in the course of a few days the work should set as hard and h.o.m.ogeneous as stone, and as damp-proof as the nature of things permits.
The three coats above referred to may be gauged as follows:--
_Coa.r.s.e Coat._--2 or 3 of sharp clean sand to 1 of Portland, to be laid about 3/4 inch in thickness. This coat is to promote an even suction and to keep back damp.
_Colour Coat._--1 of colour to 1-1/2 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 apt.i.tudes and limitations. Sgraffito work may claim a special apt.i.tude for design whose centre of aim is line. It has no beauty of material like gla.s.s, 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 tesserae or lead lines. True, hardness of design may easily result from this apt.i.tude, indeed is to a certain extent inherent to the method under examination, but in overcoming this danger and in making the most of this apt.i.tude is the artist discovered.
Sgraffito from its very nature "a.s.serts 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 pa.s.ses into expressive lines and s.p.a.ces, delivers its simple message, and then relapses into silence; but whether incised with intricate design, or left in plain relieving s.p.a.ces, the wall receives no further treatment, the marks of float, trowel, and sc.r.a.per 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 s.p.a.ces 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 apt.i.tude, 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 s.p.a.ces relieved against and slightly raised on a coloured ground; coloured lines and s.p.a.ces slightly sunk on a white surface; intricacy relieved by simplicity of line, and again either relieved by plain s.p.a.ces 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.
HEYWOOD SUMNER.
OF STUCCO AND GESSO
Few things are more disheartening to the pursuer of plastic art than finding that, when he has carried his own labour to a certain point, he has to entrust it to another in order to render it permanent and useful.
If he models in clay and wishes it burnt into terra cotta, the shrinkage and risk in firing, and the danger in transport to the kiln, are a nightmare to him. If he wishes it cast in plaster, the distortion by waste-moulding, or the cost of piece-moulding, are serious grievances to him, considering that after all he has but a friable result; and though this latter objection is minimised by Mrs. Laxton Clark"s ingenious process of indurating plaster, yet I am persuaded that most modellers would prefer to complete their work in some permanent form with their own hands.
Having this desirable end in view, I wish to draw their attention to some disused processes which once largely prevailed, by which the artist is enabled to finish, and render durable and vendible, his work, without having to part with it or pay for another"s aid.
These old processes are modelling in Stucco-duro and Gesso.
Stucco-duro, although of very ancient practice, is now practically a lost art. The materials required are simply well-burnt and slacked lime, a little fine sand, and some finely-ground unburnt lime-stone or white marble dust. These are well tempered together with water and beaten up with sticks until a good workable paste results. In fact, the preparation of the materials is exactly the same as that described by Vitruvius, who recommends that the fragments of marble be sifted into three degrees of fineness, using the coa.r.s.er for the rough bossage, the medium for the general modelling, and the finest for the surface finish, after which it can be polished with chalk and powdered lime if necessary. Indeed, to so fine a surface can this material be brought, and so highly can it be polished, that he mentions its use for mirrors.
The only caution that it is needful to give is to avoid working too quickly; for, as Sir Henry Wooton, King James"s amba.s.sador at Venice, who greatly advocated the use of stucco-duro, observed, the stucco worker "makes his figures by addition and the carver by subtraction,"
and to avoid too great risk of the work cracking in drying, these additions must be made slowly where the relief is great. If the relief is very great, or if a figure of large dimensions is essayed, it may be needful even to delay the drying of the stucco, and the addition of a little stiff paste will insure this, so that the work may be consecutively worked upon for many days.
From the remains of the stucco work of cla.s.sic times left us, we can realise how perfectly workable this material was; and if you examine the plaster casts taken from some most delicate low-relief plaques in stucco exhumed some ten years ago near the Villa Farnesina at Rome, or the rougher and readier fragments of stucco-duro itself from some Italo-Greek tombs, both of which are to be seen in the South Kensington Museum, you will at once be convinced of the great applicability of the process.
With the decadence of cla.s.sic art some portion of the process seems to have been lost, and the use of pounded travertine was subst.i.tuted for white marble; but, as the _ba.s.si-relievi_ of the early Renaissance were mostly decorated with colour, this was not important. The ground colours seem generally to have been laid on whilst the stucco was wet, as in fresco, and the details heightened with tempera or encaustic colours, sometimes with accessories enriched in gilt "gesso" (of which hereafter). Many remains of these exist, and in the Nineteenth Winter Exhibition of the Royal Academy there were no less than twelve very interesting examples of it exhibited, and in the South Kensington Museum are some few moderately good ill.u.s.trations of it.
It was not, however, until the sixteenth century that the old means of producing the highly-finished white stucchi were rediscovered, and this revival of the art as an architectonic accessory is due to the exhumation of the baths of t.i.tus under Leo X. Raphael and Giovanni da Udine were then so struck with the beauty of the stucco work thus exposed to view that its re-use was at once determined upon, and the Loggia of the Vatican was the first result of many experiments, though the re-invented process seems to have been precisely that described by Vitruvius. Naturally, the art of modelling in stucco at once became popular: the patronage of it by the Pope, and the practice of it by the artists who worked for him, gave it the highest sanction, and hardly a building of any architectural importance was erected in Italy during the sixteenth century that did not bear evidence of the artistic craft of the stuccatori.
There has just (Autumn, 1889) arrived at the South Kensington Museum a model of the central hall of the Villa Madama in Rome, thus decorated by Giulio Romano and Giovanni da Udine, which exemplifies the adaptability of the process; and in this model Cav. Mariani has employed stucco-duro for its execution, showing to how high a pitch of finish this material is capable of being carried. Indeed, it was used by goldsmiths for the models for their craft, as being less liable to injury than wax, yet capable of receiving equally delicate treatment; and Benvenuto Cellini modelled the celebrated "b.u.t.ton," with "that magnificent big diamond" in the middle, for the cope of Pope Clement, with all its intricate detail, in this material. How minute this work of some six inches diameter was may be inferred from Cellini"s own description of it. Above the diamond, in the centre of the piece, was shown G.o.d the Father seated, in the act of giving the benediction; below were three children, who, with their arms upraised, were supporting the jewel. One of them, in the middle, was in full relief, the other two in half-relief. "All round I set a crowd of cherubs in divers att.i.tudes. A mantle undulated to the wind around the figure of the Father, from the folds of which cherubs peeped out; and there were many other ornaments besides, which," adds he, and for once we may believe him, "made a very beautiful effect." At the same time, figures larger than life, indeed colossal figures, were executed in it, and in our own country the Italian artists brought over by our Henry VIII. worked in that style for his vanished palace of Nonsuch.
Gradually, stucco-duro fell into disuse, and coa.r.s.e pargetry and modelled plaster ceilings became in later years its sole and degenerate descendants.
Gesso is really a painter"s art rather than a sculptor"s, and consists in impasto painting with a mixture of plaster of Paris or whiting in glue (the composition with which the ground of his pictures is laid) after roughly modelling the higher forms with tow or some fibrous material incorporated with the gesso; but it is questionable if gesso is the best vehicle for any but the lowest relief. By it the most subtle and delicate variation of surface can be obtained, and the finest lines pencilled, a.n.a.logous, in fact, to the fine _pate sur pate_ work in porcelain. Its chief use in early times was in the accessories of painting, as the nimbi, attributes, and jewellery of the personage represented, and it was almost entirely used as a ground-work for gilding upon. Abundant ill.u.s.tration of this usage will be found in the pictures by the early Italian masters in the National Gallery. The retables of altars were largely decorated in this material, a notable example being that still existing in Westminster Abbey.
Many of the gorgeous accessories to the panoply of war in mediaeval times, such as decorative shields and the lighter military accoutrements, were thus ornamented in low relief, and on the high-cruppered and high-peaked saddles it was abundantly displayed. In the sixteenth-century work of Germany it seems to have received an admixture of finely-pounded lithographic stone, or hone stone, by which it became of such hardness as to be taken for sculpture in these materials. Its chief use, however, was for the decoration of the caskets and ornamental objects which make up the refinement of domestic life, and the base representative of it which figures on our picture-frames claims a n.o.ble ancestry.
Its tenacity, when well prepared, is exceedingly great, and I have used it on gla.s.s, on polished marble, on porcelain, and such like non-absorbent surfaces, from which it can scarcely be separated without destruction of its base. Indeed, for miniature art, gesso possesses innumerable advantages not presented by any other medium, but it is hardly available for larger works.
Time and s.p.a.ce will not permit my entering more fully into these two forms of plastic art; but seeing that we are annually receiving such large accessions to the numbers of our modellers, and as, of course, it is not possible for all these to achieve success in, or find a means of living by, the art of sculpture in marble, I have sought to indicate a home-art means by which, at very moderate cost, they can bring their labours in useful form before the world, and at the same time learn and live.
G. T. ROBINSON.
OF CAST IRON
Cast iron is nearly our humblest material, and with a.s.sociations less than all artistic, for it has been almost hopelessly vulgarised in the present century, so much so that Mr. Ruskin, with his fearless use of paradox to shock one into thought, has laid it down that cast iron is an artistic solecism, impossible for architectural service now, or at any time. And yet, although we can never claim for iron the beauty of bronze, it is in some degree a parallel material, and has been used with appreciation in many ways up to the beginning of this century.
Iron was already known in Suss.e.x at the coming of the Romans. Throughout this county and Kent, in out-of-the-way farm-houses, iron fire-backs to open hearths, fine specimens of the founder"s art, are still in daily use as they have been for three hundred years or more. Some have Gothic diapers and meanders of vine with heraldic badges and initials, and are evidently cast from models made in the fifteenth century, patterns that remained in stock and were cast from again and again. Others, of the following centuries, have coat-arms and supporters, salamanders in the flames, figures, a triton or centaur, or even a scene, the Judgment of Solomon, or Marriage of Alexander, or, more appropriately, mere pattern-work, vases of flowers and the like. However crude they may be, and some are absurdly inadequate as sculpture, the sense of treatment and relief suitable to the material never fails to give them a fit interest.
With these backs cast-iron fire-dogs are often found, of which some Gothic examples also remain, simple in form with soft dull modelling; later, these were often a mere obelisk on a base surmounted by a ball or a bird, or rude terminal figures; sometimes a more delicate full figure, the limbs well together, so that nothing projects from the general post-like form; and within their limitations they are not without grace and character.
In Frant church, near Tunbridge, are several cast-iron grave slabs about six feet long by half that width, perfectly flat, one with a single shield of arms and some letters, others with several; they are quite successful, natural, and not in the least vulgar.
Iron railings are the most usual form of cast iron as an accessory to architecture; the earlier examples of these in London are thoroughly fit for their purpose and their material; st.u.r.dily simple forms of gently swelling curves, or with slightly rounded reliefs. The original railing at St. Paul"s, of Lamberhurst iron, is the finest of these, a large portion of which around the west front was removed in 1873. Another example encloses the portico of St. Martin"s-in-the-Fields. The railing of the central area of Berkeley Square is beautifully designed, and there are instances here, as in Grosvenor Square, where cast iron is used together with wrought, a difficult combination.
Balcony railings and staircase bal.u.s.trades are quite general to houses of the late eighteenth century. Refined and thoroughly good of their kind, they never fail to please, and never, of course, imitate wrought iron. The design is always direct, unpretentious and effortless, in a manner that became at this time quite a tradition.
The verandahs also, of which there are so many in Piccadilly or Mayfair, with posts reeded and of delicate profiles, are of the same kind, confessedly cast iron, and never without the characterising dulness of the forms, so that they have no jutting members to be broken off, to expose a repulsive jagged fracture. The opposite of all these qualities may be found in the "expensive"-looking railing on the Embankment enclosing the gardens, whose tiny fretted and fretful forms invite an experiment often successful.
It must be understood that cast iron should be merely a flat lattice-like design, obviously cast _in panels_, or plain post and rail construction with cast uprights and terminal knops tenoned into rails, so that there is no doubt of straightforward unaffected fitting. The British Museum screen may be taken to instance how ample ability will not redeem false principles of design: the construction is not clear, nor are the forms sufficiently simple, the result being only a high order of commonplace grandeur.