Georges de Récy

“ Deep carmine constitutes a rich colour for groundwork, and is produced by using bright red over potash and deepening the effect by rubbing.
In planning a decoration, the artist has generally some special effect in his mind which he wishes to reproduce. It is not unusual, however, for the result to be totally different from what is anticipated, since uncertainty constitutes one of the charms of the art of colouring leather. These failures, as they may be considered from one point of view, often produce interesting effects and sometimes lead to valuable discoveries. ”

“ Outlining is the most delicate process in leather mosaic. When well carried out it should be impossible to distinguish the line where the inlay joins the groundwork. The extreme edge of the inlaid leather is pressed into the groundwork by means of a tool invented by Mons. Aumaître, producing a fine line the breadth of the edge of the tool selected. This tool, called an outliner (Fig. 27) , has two blunt ends, one rounded and the other square, and is flat on one side and rounded on the other. ”

“ In cut decoration a better effect can be obtained with this leather than with thinner skins, and being very firm, it is equally suitable for modelling.
Morocco leather, which is mostly of the kind called “Cape morocco,” is goat-skin with a grained surface produced by pressing hard seeds upon the skin while it is still damp from the tanning. For bookbinding and similar purposes this grain is crushed by pressing hot plates heavily on the surface. The only way of decorating leather so treated is by an inlay (or literally onlay) of skins of other colours, and is known as Leather Mosaic. ”

“ Designs in the modern style, or Gothic designs in the style of the fifteenth century, or those based on the Arabic decoration of the best period, are much to be preferred; in the last two styles punches used with a hammer will greatly assist in lowering the groundwork, so that the design stands out in relief without the necessity of stuffing it, as in embossed work. By introducing gouache or bronzes into the impressions made with the punches, rich effects of colour can be produced. ”

“ With certain soft leathers, if the colour has not sunk in deeply, rubbing with the finger alone will give it great brilliancy; with other leathers the rubbing will produce an effect in proportion to the degree of porosity of the skin. It should always be done before the colour is dry, but not until it has penetrated sufficiently into the leather not to return to the surface with the pressure. ”

“ The circumstance already explained, that in leather decoration dyes may be used one over the other, enables interesting effects to be produced.
A design of sea, with seaweed and fish, can be effectively rendered entirely with sulphate of iron of varying strength. A weak solution is washed evenly over the whole; the waves are then drawn in with a flat brush dipped in a stronger solution, and the dark outlines afterwards bleached with acid where they border the first tint. ”

“ Punches are steel or brass tools, having at the point a design cut in relief or in intàglio, which are impressed on the leather either by the hand alone or with a hammer The design is thus reproduced on the leather with the impression contrary to that on the tool. For hand pressure only, they should be fixed in wooden handles to afford greater grip and power. They may be used hot; the design will then appear darkened on the leather.
Punches are also employed in tooling with gold leaf, or in burnishing the impression of their surface on groundwork gilded with shell gold. ”

“ When it is to occupy a definite position, forming the framework of a design, for instance, it is laid upon the groundwork exactly in the right place and then given a sharp turn in a copying-press,50 great care being taken that it does not get displaced during the operation. Owing to the thickness of the supporting paper, this will be sufficient to mark the outline of the design on the groundwork. Some very smooth starch paste is then applied with a flat brush on the exposed side of the cut out leather, care being taken that every part, however small, is thoroughly pasted. ”

“ The leather should be neatly and sharply cut out for open-work decoration, and placed over a groundwork of leather, stuff or metal: the last material is well adapted by its contrast of colour to show up the ornament laid over it. Open-work leather is a good material for hangings, and when destined for this purpose the design is sewn on the groundwork of leather or stuff with a sewing-machine, or stuck with gutta-percha. ”

“ When the dye has sunk in, the decolorant can be easily applied with a paint-brush. On modelled leather dyed bronze green, a rag or piece of cotton-wool dipped in decolorant and quickly passed over the relief, will lighten the colour and produce the effect of bronze with the exposed72 parts rubbed lighter by use. Should the effect of the acid be too strong, the colour may be again deepened by washing the leather over with a yellowish gold stain, which will only take effect on the relief, since it will merge into the darker colour of the rest of the work. ”

“ Since about 1860 sheepskin as sheepskin is hardly to be found. Sheepskins are grained in imitation of other leathers and these imitation-grained leathers are generally found to be in a worse condition than any of the other bindings, except, perhaps, some of the very thin calf skin. Undyed modern pigskin seems to last well, but some coloured pigskin bindings had entirely perished. Modern leathers dyed with the aid of sulphuric acid are all to be condemned. In nearly every case Russia leather was found to have become rotten, at least in bindings of the last fifty years.... ”

“ For shaded groundwork diluted colour is applied with a sponge or pad worked over the leather with a circular movement, and the uniform tint thus obtained is darkened as required by further applications with stronger colour. In shading a ground from one colour to another, as for example from dark olive to malachite green, orange red and pale yellow, the edge of each colour, as it is put on, is covered with a piece of thick paper, which must be firmly held in place, in order to prevent the colours mixing where they come together. ”

“ After cutting the design on the leather, the whole surface is washed over with potash or any other dark stain, a coat of paste is then applied and immediately wiped off, so that some of it only remains in the hollows. When the paste is dry, some rather liquid gouache is washed over and run into the lines, any remaining on the surface being removed by vigorous rubbing with a damp rag. The same process may be applied to the hollows of punched leather. In using bronzes or gold in powder, some spirit varnish or specially prepared varnish is necessary to make them adhere. ”

“ The lines must be cleanly cut in order that the subsequent operation of outlining may be successfully accomplished. With every care in cutting out, it may sometimes be found in detaching the cut portion that a small thread of the leather remains unsevered. In this case it should be neatly cut through, and on no account may it be pulled to make it give way, which would result in spoiling the design by either tearing or stretching the leather. When cutting out a design on a large scale it is not possible to hold the work in the manner just described ”

“ It is an essential qualification that nothing of a fatty nature be used in their preparation. The tanning process of the best skins, whether with a glossy surface artificially obtained by rolling or with a dull surface, should be a very simple one. Oak and sumach tannins (used especially for morocco leather) are those which best preserve the suppleness and capillarity of leather. The susceptibility of its colour to alteration from exposure16 to light is greatly influenced by the materials used in tanning. Oak wood and chestnut are the tannins least influenced by light. ”

“ When the inlay is of white or very light leather, it is extremely difficult to conceal any joins occurring in the middle of lines; care must therefore be taken that there are as few joins as possible, and that they are arranged at points where they will easily disappear in lines of the design going in an opposite direction. ”

“ Calf varies greatly in thickness and colour. It should be noted that in carved and modelled work the advantages of great malleability in the material are more than counterbalanced by the disadvantages; durable results cannot be obtained with very malleable leather which yields easily to the tool, and since high relief can be worked without difficulty in comparatively thick leather by damping it, its use is much to be preferred.
Ox-hide is frequently as thick as strong cardboard and is the ideal leather for carving, hammering and pyrogravure. ”

“ The pencil possesses the additional advantage that it can be given a very fine point where an extra thin and sharp outline is required. Doubling the outline by going over it twice should be avoided. From time to time the tracing-paper or linen should be raised to see that the design is being well marked on the leather. The outline should be dark; when it comes light it is a proof that the leather is too dry and requires damping again. ”

“ Ordinary water-colours based on glycerine or albumen can be used in the decoration of leather, but are recommended only for colouring small parts of a design, partly because liquid colour is more easily applied over large surfaces, and partly because, being less transparent, they do not lend themselves to the process of rubbing which plays so important a part in patine. Oil or spirit colours, on the other hand, possess a transparency which allows of their being used over a ground coloured with a different medium. ”

“ When curved lines are to be cut, the left hand must be used to turn the leather so as to present it in the most favourable position for the operation of the blade. The third knife (Fig. 6) is held like a graver with the handle supported against the palm of the hand and is pushed forward (Fig. 7) . It is useful in cutting curved lines over a large surface. The depth of the incision should vary according to the effect22 to be produced by the subsequent operation, but it should never exceed a third of the thickness of the skin. ”

“ While on the subject of gold groundwork made with gold or silver leaf or tin-foil covered with varnish to imitate the colour of gold, it is curious to note how far back in the history of art its origin can be traced ”

“ Stencilling is another process by which portions of the leather forming the ornament are reserved from the dye used in colouring the ground. The design is cut out of a very thin sheet of copper or tin. A large short-haired brush [13] is used to take the dye from a plate, or pad, and is then rubbed very lightly over the stencil firmly fixed on the leather. Only the parts unprotected by the stencil will take the colour. The brush must not be too full or the dye would have a tendency to run under the stencil. The most suitable dyes are glycerine inks and marking inks containing nitrate of silver. ”

“ In all ages man has sought to develop to their fullest extent the possibilities of splendour in the materials of his dress, and an important place in the wardrobes of our early ancestors was filled by skins shorn of hair, thus lending themselves easily to decoration in many different ways. ”

“ It is better not to use ordinary steel which, when the leather is wet, might cause it to become stained through the rusting of the tool occasioned by the materials used in tanning. It may also be mentioned here that when using acids for patine, [5] steel tools should be kept away from the work. Hydrochloric acid in particular will rust them so badly in a single night as to make them unusable unless they are repolished. ”

“ Fresh market skins, dry skins, or wet salted skins are much to be preferred to those known as ‘drysalted,’ since the crystallization of the salt which takes place in the drysalting process, tends to weaken the structural fibre of the pelt. No tainted or putrefied skins, even if only slightly affected, are suitable for the manufacture of bookbinding leather, both for the same reason, and because the weakness of grain so produced leads to uneven dyeing. ”

“ When it is too large to put into a copying-press, it should be laid upon a flat table and a sheet of nickelled or very smooth zinc placed against the part to be decorated. The cardboard known as Carton Jacquart may be substituted for the zinc, but there is a risk that the moisture of the paste penetrating the leather may cause it to swell, notwithstanding its glaze. The zinc plate or the board should not be smaller than the leather, for in that case the pressure would produce a ridge round its edge. ”

“ In the old decay the leather becomes hard and brittle, the surface not being easily abraded by friction. The older form is specially noticed in calf-bound books, tanned presumably with oak bark. The new form affects nearly all leathers, and, in extreme cases, seems absolutely to destroy the fibres. Another form of deterioration, more noticeable in the newer books, renders the grain of the leather liable to peel off when exposed to the slightest friction. ”

“ The education of the eye is a considerable factor in the conventional interpretation of natural forms. The artist cannot do better than to study the ancient Japanese school, which has found such favour with the initiators of the so-called “Modern Art,” and which affords the best examples of balance in design in its rejection of unnecessary detail in the interpretation of natural forms. ”

“ Permanganate of potash is supposed to dye a mouse-grey colour, but it is most uncertain in its action, as it depends entirely on the porosity of the leather. Xanthin and catechol browns are pleasing in appearance, but their effect is less rich than that obtained with potash. They become improved by hard rubbing with encaustic.
Sulphate of iron has a strong and persistent odour and is also somewhat injurious. It is useful, however, and produces a colour varying from a light shade to an intense66 violet black. When used over potash, a dead black is obtained. ”

“ We must absolutely condemn the use of any but mild vegetable acids in souring or scouring the leather, or in the dye bath, and as far as possible would avoid the use of acids and alkalis on tanned leather, both being equally injurious. ”

“ The nomadic races, described to us as at first riding their horses barebacked to the conquest of the West, soon adopted ornamental trappings more suited to their position as conquerors, as shown by the marvellous mosaics of piqué leather which from an early date constituted the foundation of the war-like equipment of the Tartars and Moguls. ”

“ The use of oxalic acid for washing backs of books, or of leather for bookbinding, is fatal to their durability....
“The sprinkling of leather with ferrous sulphate (green vitriol) , either for the production of ‘sprinkled’ calf or ‘tree’ calf, must be most strongly condemned, as the iron combines with and destroys the tan in the leather, and free sulphuric acid is liberated which is still more destructive.... ”

“ Any skin may be used for the groundwork of leather mosaic, but morocco, and especially the kind called Cape morocco, is generally preferred, because of the grained surface which shows up the inlaid decoration to the best advantage. ”

“ A hammer, though useful in working certain punches which depend upon being deeply impressed to produce a good effect, requires great sureness of hand when used as described above, to prevent overstepping the limits of the outline, and punches in wooden handles are much to be preferred for this work. Too deep an impression is avoided by their use, and, by guiding the end of the punch with the left hand, it can be placed more surely in the right position and worked by the steady pressure of the wrist. (Fig. 16.) ”

“ The leather is first damped all over and the colour then applied in a succession of even washes. Care must be taken not to unduly darken any part of the leather by using too much colour, bearing in mind that different parts of the skin will vary greatly in porosity. In colouring groundwork with various superposed tints, the actual results are often entirely different from those one has had reason to expect. ”

“ There are numerous other styles appropriate to the decoration of leather coffers.
In the decoration of large surfaces, such as the panels of wall-hangings, the artist is cautioned against the abuse of detail, frequently the stumbling-block of the beginner. He is recommended to exercise a wise restraint in his composition, and to avail himself of the numerous resources of the conventional art of the modern school more particularly in their application to the ornamentation of large surfaces. ”

“ Shell gold is applied with a slightly damped brush and, when dry, may be burnished with an agate or punch; the design of the punch will stand out in bright gold on a ground of dull gold. The pressure of the wrist is sufficient to work the punch and a hammer should not be used.
There is an interesting field for the artist’s enterprise in the discovery of new processes for the decoration of leather by means of colours and bronzes. ”