WE have made mention of the practice and great antiquity of fresco painting in the previous chapters on Greek and Roman art, and we have seen that in primitive Greece the interior walls of the edifices were coloured in broad flat tints, and also decorated in a pictorial manner on the wet plaster as well as on the dry surfaces. The wet or buon fresco system and the dry or secco method, as well as wax or encaustic painting, were each employed by the ancients in the decoration of walls, both in the nature of plain painting of large surfaces, panels, and bands of flat colouring, and in the pictorial compositions of mural decoration.
In the first chapter of this volume it is mentioned that secco, or the system of painting on dry walls in tempera, was the universal method that obtained in ancient Egypt. It may be also mentioned that wax painting was practised by the Egyptians, but this was in a later period, during the Greek occupation, when, about 330 B.C., wax, or encaustic painting, was introduced into Egypt.
We have also seen that tempera painting was largely practised by the Chaldæans, Assyrians, and the ancient Persians, but in addition to this method of wall decoration, the Mesopotamian people developed the magnificent art of enamelled tile decoration, which probably had its birth in Chaldæa, but blossomed into a fuller and maturer beauty, as a most perfect and enduring form of wall decoration in Persia during the fifth and sixth centuries B.C.
Tempera or distemper painting is the oldest historical method of painting that is known to us, whether employed as in wall decoration, or in other forms of pictorial art, while fresco painting, on the wet lime plaster, as far as we can say, dates from at least 1500 B.C., the conjectured period of the foundation of the Minoan palace at Cnossus in Crete, where Dr. Evans, in 1900-1902, found some portions of lime-plastered walls that were decorated in the buon fresco method. Fragments of ancient fresco painting have also been found by Dr. Schliemann when excavating on the site of the ancient palaces of the pre-Hellenic Mycene and Tiryns of primitive Greece, and still earlier examples of fresco decoration have been found in prehistoric Thera, one of the Grecian isles.
Painting in fresco, on the wet lime plaster, is therefore of great antiquity in Europe, and has been practised in conjunction with ” fresco-secco,” or ” dry ” fresco, from very early times. For example, the greater portion of the old wall surfaces would be decorated in flat tints of selected colours, the colours being sometimes mixed with the finishing coating of lime plaster, before the latter was spread on the wall, or in other cases the colour mixture would be directly applied in the ordinary way to the surface of the wet plaster. In either case the object of obtaining a flat ground colour of the desired tint would be achieved. On such coloured grounds the primitive Greek artist would execute his decorative subjects, which usually consisted of ornamental forms, or crude representations of the human figure, birds, animals, and floral forms, and this decoration was sometimes painted in a direct method on the coloured grounds while the plaster was wet, the true fresco method, but more often the wall surface was allowed to dry before the decoration was executed. But before beginning this decorative painting the dry wall would be well saturated with lime water, and the colours used in a similar way as in fresco, with water only as the medium. This method of wall painting is known as ” fresco-secco,” but it is not so permanent as buon fresco. It must be understood that the term ” fresco-secco ” is ” lime painting ” as practised by the ancients, and is the only kind of fresco mentioned by Theophilus and other old writers, and that the term secco, as used by Vasari, refers to tempera painting in which there is no lime used with the colours, but egg or glue size only.
The alternative method of painting on the dry wall was in tempera, or distemper, where the colours were tempered with size, made from glue, parchment, gum tragacanth, eggs, or milk, etc. Sometimes the wall decorations of primitive Greece, and of the classic period, as well as those of the Pompeian and Roman edifices, were executed in the above three methods, each method being used on different parts of the same wall surface. Also the artist, as it often happened, could not always give the required finish to certain subjects, or parts of the decoration, in the limited time that the plaster remained in a wet state, so he would then finish his task at leisure in secco or tempera, by afterwards working over the fresco surface. Small panels, and other limited spaces on the wall were painted in buon fresco, as these small portions could be finished properly before the plaster would dry, but larger schemes of decoration, or large surfaces, were usually painted in a more leisurely manner in fresco-secco, or tempera. This was the practice usually adopted by the Greeks, and by the Pompeian artists.
The finishing of fresco paintings in secco or tempera was practised by nearly all subsequent painters in Italy up to the sixteenth century, though it cannot be said that it has ever proved successful. It was generally condemned as a bad practice, and especially so by the later and stricter schools of Italian fresco painting. Wall paintings executed in this mixed method of the dry and wet fresco have proved to be far less permanent than those which have been wholly executed in buon or wet fresco.
Although we have proof that buon fresco is of great antiquity, it was more confined, in the practice of the ancients, to small spaces or on panels in the walls that could be finished in about the space of a day’s time, and such small spaces would not consequently show any joinings, which usually marked out the spaces or divisions on the wall, that we see in the buon fresco paintings of the fourteenth and fifteenth centuries in Italy. We may, therefore, be certain that if an old wall painting of a moderately large surface does not show any joinings of the plaster, or intonaco, it has not been painted in buon fresco, for in this method of painting only a portion of the wall surface, limited in size to that amount of surface that can be properly finished in a day’s time, can be worked on while the plaster is wet, and any portion which cannot be finished off in the one day’s painting must be cut away and a fresh portion laid on, and joined up to it for the next day’s work.
Such fresco-painted walls that show no joinings that would indicate the extent of a day’s work, have been painted in fresco-secco, a method we have already spoken of, where the whole surface has been prepared all of one piece, by laying on a plaster ground composed of lime and river ‘sand, and in some cases marble dust was added. The mixture of this plaster ground has varied a good deal as to the quantities of lime and sand. Some-times it has been used in the proportion of three parts of sand and two of lime, and in other in-stances, three-quarters of sand and one-quarter of lime, or one-third of lime to two-thirds sand, and some artists have used the lime and sand in equal proportions. We might say that the pro-portions may vary considerably without affecting the durability of the wall surface, provided that the plaster mixture is not made too ” fat ” with rather much lime, or too poor with an undue quantity of sand, but experience will teach the artist to work on a plaster surface which contains a much greater proportion of sand than of lime, for on what may be called a poor or sandy surface he can better afford to use his colour in an impasto, and can also venture to use lime in them more freely than he could do on a rich or ” fat ” plaster. Other great gains on working on a poor or sandy surface are that the finished work will appear more transparent, rich, and luminous, which are the distinguishing qualities of veritable fresco over all other methods of wall painting.
The same kinds of plaster grounds we have been describing have been used in almost every period of art history from the earliest times, both for the wall surfaces on which the fresco-secco paintings were executed, and for the intonaco or final plaster ground in buon fresco. It may be pointed out that the dry surface intended for fresco-secco was usually made very smooth by polishing it with pumice stone before it was saturated with lime water, preparatory to the execution of the paintings, and that on these surfaces, which showed no joinings, such work as ornamental decorations could be executed more freely than in the buon fresco method, where the joinings would interfere with the flow and freedom of drawing that characterizes ornamental forms. For the latter kind of painting, therefore, the secco method is preferable to buon fresco, though it is inferior to it as regards permanency.
The early Italian artists painted in secco like the Pompeian decorators, for buon fresco painting, which is required to be executed in portions, was not the universal practice in Italy until about the beginning of the fifteenth century, though a few wall paintings were done in this method earlier than this.
Prior to the middle of the fifteenth century, and in instances even later than this date, the Italian fresco painters would appear to have followed out a most cumbersome method of executing wall paintings on the wet plaster, and this procedure has even been recommended, and described by Cennini in the sixty-seventh chapter of his Treatise on Painting. The method in question almost amounted to the painting of two works, one on the top of the other, with a coating of plaster between them. It is true that the first painting was executed roughly as a shaded drawing on the first rough mortar coating that was applied to the wall, or on the second, if three layers of plaster were used. The final coating, on which the finished fresco was painted, was called the intonaco, and the one immediately under it was the arricciato. The intonaco was in some cases very thin and almost composed of the pure lime itself, but mostly it was a mixture of lime and fine river sand, while the arricciato was a very coarse mixture of lime and sand.
In the method mentioned above the Italians of the thirteenth century and later appeared to have worked from a small design, instead of a full-sized cartoon, which they enlarged by means of squares from the small sketch to the full size on the arricciato or rough plaster. This they outlined usually in red, shading and even tinting most of the design in colour on this rough surface ; afterwards they covered this with the intonaco or last layer of this plaster, taking care, however, to place a counterpart of each portion of the design over the one first drawn out on the underneath rough surface, the squared lines on which acted as a guide to show the artist where to place the design on the intonaco, which layer of plaster must have obliterated the underneath painting. We can only imagine, that unless the artist went to the extraordinary length of re-drawing his design on the surface of the final intonaco, he must have had a tracing made from the enlarged sketch originally drawn on the rough plaster and transferred this to his final painting surface, otherwise he could not possibly have seen the original enlarged drawing if a coating of plaster, however thin, or lime only, had intervened between his vision and the underneath plaster. In later times this tedious method was abandoned, when tracings were made from full-sized cartoons and transferred to the wall, either by pouncing, or by the use of a pointed stylus, which made an engraved outline on the surface of the soft intonaco.
As a rule the Italians laid on a slight tint of verde colour before painting in the lights and shades of the flesh portions of their frescoes, and they also followed out this practice in the tempera paintings. Some exceptions to this are seen in the frescoes by the Sienese painters, as in the works by the Lorenzetti and Antonio Veneziano in the Campo Santo at Pisa, and in the Spanish Chapel in St. Maria Novella, at Florence, where the lights, shadows and semitones of the flesh are painted directly on the white grounds without any verde preparation being used. It was also a common practice to lay a red ground preparation for all blue draperies, and in some cases for blue skies. Neutral greys have also been used as preparatory ground colours for blues. The choice of red as a ground for blue may have been due to the possibility of counteracting the cold tone of that colour, which is so difficult to manage in fresco in point of harmony with the other and warmer colours. It may be pointed out that in the early, and also in later times, when the art of fresco painting was in its zenith in Italy, nearly all the blues of draperies and of skies were painted in tempera, when the plaster surface was dry, and almost invariably on red grounds.
Many works of Giotto, Taddeo Gaddi, his pupil, Fra Angelico, Benozzo Gozzoli, and other Italian frescanti are now only outlines, with the exception of the light verde of the preparatory flesh colour, and the red preparation of the blue draperies and skies, or of such portions that were intended to be finished in blue. We may, therefore, infer from this that the blues and other colours which have disappeared have either been painted in tempera after the preparatory ground colours were dry, or else the vanished colours had been applied to the intonaco surface when the latter was too dry, and in consequence have not been incorporated into the plaster surface, while on the contrary the ground or preparation colours, which still remain, had been painted on the wet surface very soon after the intonaco was freshly laid on the wall, and this is sufficient to account for their permanency.
We may give one or two examples out of many which may illustrate our statements ; for instance, the fresco by Giotto, of St. Mary of Egypt, in the Chapel of the Podesta at Florence, is one of many others where the usual preparation of verde is all that remains of the flesh tints, and the red preparation of , the Virgin’s mantle, which must have been originally finished in blue ; also, in the celebrated fresco of the Crucifixion by Fra Angelico in St. Marco, at Florence, the upper part of the sky is now a dark purplish red, which originally must have been blue, but the latter colour has scaled off, leaving the preparatory red ground. As a rule, large surfaces, such as skies, in fresco were always painted in tempera, or in simple water colours, and not in buon fresco, except in the limited way of laying on the wet plaster some kind of preparatory tint to tone down the white intonaco surface, previous to the execution of the final painting.
Time, damp, dirt, and the restorers, we are informed, have all been responsible for the present decayed state of buon fresco paintings everywhere, but all of these agencies have not been so much the cause of the deterioration of frescoes, as the imperfect technical methods of their execution, for it is quite evident that those fresco paintings which still remain in a good state of preservation after lasting four or five centuries, have in every case been executed in sound technical methods of painting on the wet plaster, where the work on each portion was finished in one day’s time, while the plaster ground was still wet, and no after-painting or retouching has been attempted, either in fresco-secco or in tempera. It may be mentioned that genuine buon fresco paintings may be washed with water, or otherwise cleaned, without injuring the colours, while wall paintings in secco or tempera cannot be washed or cleaned without removing some of the colour in the process.
When we know that it was a common practice with the majority of the Italian painters to finish their buon fresco work in tempera, and in nearly every case to paint the blue draperies and skies in this medium, we cannot be surprised that such portions have been destroyed by subsequent cleanings, and the effect of damp, or moisture on the surface.
If the pigments used in buon fresco painting are confined to a selection of those obtained from such simple earths and minerals that will permanently withstand the action of the lime, and if the painting is completely finished within four or five hours after the fresh intonaco is laid on the wall, there is no reason why this method of painting should not be the most permanent of all methods of mural decoration. Fresco so executed will defy the surface damp of the atmosphere, and the colours will hardly undergo any change for centuries, provided they have been thoroughly incorporated in the wet plaster.
For a list of the colours that may be safely used in fresco, and for further information on this subject the reader is referred to the author’s treatise on Fresco Painting, Its Art and Technique, 1909, where the system of the modern Spirit Fresco is also described.