Some Remarks Concerning 'Sinopie'

 

Detail of the sinopia of an Annunciation by Puccio Capanna (or, Pace di Bartolo) in the Pinacoteca Comunale di Assisi (Photo: the author)1

What are 'sinopie'? Sinopie are, to put it simply, drawings made with a particular red paint using a pigment which originated near the Black Sea at a place then called Sinope (now, Sinop), hence sinopia; the particularity of this word is that it refers nearly always to the preparatory drawing made by artists as a step in the process of fresco painting. And why are they, sinopie, of any interest, of any importance? They are important because they reveal to us, after hundreds of years of being 'hidden', the creative thoughts, not to say skill, of the artists who made them.

In Italy, between about 1300 and 1500 2, the painting of frescos was, to all intents and purposes, the principal means of expression for painters, not to mention their principal source of income; frescos are normally painted on walls, very commonly on the walls of churches. But they could be, and were, painted on the interior walls of town halls and private houses for example, as well as on the exterior of buildings, both public and private. The other main way for painters to earn a living was by painting altarpieces - usually for churches - and these, unlike frescos, were painted on wooden panels; there was also a difference in the paint used: fresco uses pigment mixed with water, while tempera is pigment mixed with egg or glue. The especial quality of fresco (a fresco or affresco in Italian) is that the water paint is absorbed into the plaster (the intonaco) while it is still damp and, through a chemical reaction with the lime in the plaster, becomes an integral part of that surface; it does not sit 'on top of' the plaster, it is part of it.

The painting of a fresco requires several steps, each of which is crucial to the physical longevity of the work, that is, to the physical integrity of the work as a manufacture; the 'artistic' result, as always, depends on the character and skill of the artist. The first step was the preparation of the wall to be painted on; this entailed the application of a layer of rough 'plaster', known as arriccio; this layer, rather rough in texture, separated the wall from the painting surface as well as providing a foundation for that surface; this latter, a smooth plaster layer known as the intonaco was the layer on which the actual image would sit - or, better, into which it would be absorbed. It is between these two layers of preparation, the arriccio and the intonaco, that we find the sinopia.

If the sinopie are hidden - under the intonaco - how do we know about them? People involved with the making of frescos (painters and patrons) have, of course, always known about them; however, in modern times, many sinopie have come to light because of damage to the upper layer, that is, to the image itself. One of the most important, and destructive, examples of this was the great flood which occurred in Florence on November 4th, 1966; that flood, which took the level of the Arno River several metres above normal ground level, did untold damage to thousands of works of art, not only to frescos. However, as a direct result of this flood, many frescos, dating to pre-Renaissance times and after, were detached from the walls on which they had been painted and restored, some obviously with more successful results than others. In the process of lifting a fresco from a wall (see below), that is to say, the top layer with the image 'in' it, the arriccio is revealed and with it, the sinopia. Let's have a look at some examples.

The sinopia of  a detail of Buffalmacco's painting (1336-41) the Tebaide  in the

Museo delle Sinopie, Camposanto, Pisa

(Image courtesy of Wikimedia Commons, photo credit Sailko)

Given the period in which this work was made, the late-Medieval, the drawing is astoundingly 'modern' and of such high quality. For our purposes, the important point is the very existence of the sinopia; not only does it confirm the use of this technique at that time, so long ago, but, as mentioned earlier, it allows us a glimpse into the mind of the artist, of Buffalmacco, as he devises his composition (see the article in this blog entitled Buffalmacco at Pisa). This is because, although compositional drawings on paper do exist from this time, they are extremely rare: and this because normally, the composition and the individual figures were developed there and then, on the arriccio itself. The painter would first sketch his ideas onto the arriccio in charcoal then, once happy with this, go over the drawing with the sinopia, the red paint from which the drawing takes its name. The charcoal would then be dusted off in readiness for the application of the intonaco; the intonaco, an extremely fine plaster, was translucent enough to enable the painter to see his drawing, the sinopia, underneath.

Madonna and Child with Angels, sinopia, early 15th century, by Paolo Schiavo (born Paolo di Stefano  Badaloni), 1397 - 1478; 

in the Church of Santi Apostoli, Florence (Photo: the author)

This superb drawing, controlled with a central vertical line as suggested by Cennino Cennini 3, again demonstrates the extraordinarily high level of skill attained by Italian masters, this time during the Renaissance itself. Like many such sinopie, but not all, there is a relatively high degree of detail, especially in the folds of the garments worn by the Madonna and the Christ Child. Again, as with too many frescos, there is obvious damage to several parts of this work, notably on the left side and along the bottom (the church, Santi Apostoli, is situated only metres from the Arno). Frequently, damage is due to water leaching through the walls on which frescos sit, producing salts which eventually seep through the plaster and destroy the colour. Sometimes though, the damage was deliberate, as when tastes changed and even very important pictures - such as by Giotto - were either hacked off the wall or whitewashed. This latter expedient however has occasionally worked in the opposite direction insofar as certain paintings, such as the Giottos in Santa Croce in Florence, were unintentionally preserved precisely because they were only whitewashed - then to be rediscovered many years later! (As also occurred incidentally with the Byzantine mosaics in Hagia Sophia in what was Constantinople, now Istanbul). Sometimes as well, war is to blame; but sometimes, natural disasters such as earthquakes are the culprits.

Sinopia of the fresco San Girolamo penitente (The Penitent Saint Jerome), c. 1492

by Bartolomeo della  Gatta (born Piero di Antonio Dei), 1448 - 1502. (Photo: the author)

The Penitent Saint Jerome, fresco by Bartolomeo della Gatta, c 1492 (Photo: the author)

Both this fresco and the sinopia above are in the Museo Diocesano di Arte Sacra, Arezzo

The fresco above, a very large work - slightly damaged and once in the cathedral in Arezzo - is quite a bit more developed than its sinopia (also above) might have led one to anticipate. In fact, in this case, especially compared to the two previous sinopie, the drawing is little more than a sketch and seems not to include the smaller 'life-stories' dotted around the top of the finished fresco. The completed painting is a powerful work, beautifully coloured and shows a typical view of Saint Jerome chastising himself in his desert cave; we know who the saint is because of his 'attributes', in this case, the lion and the (anachronistic) cardinal's hat beside him. Bartolomeo della Gatta was a monk as well as, according to Vasari, a polymath (but who wasn't in those days!), being in addition to a painter, an architect, a musician and an illuminator of manuscripts. Quite a lot of well-known artists were in fact monks, friars or priests, including Beato Angelico, Filippo Lippi, Fra Bartolomeo and Sebastiano del Piombo, to name a few.

As far as the fresco technique is concerned, the sinopia was not the only way of working from a drawing, although it would seem to be the oldest. As the 15th century became the 16th, two other ways of preparing a drawing for a fresco were developed. The first was the so-called spolvero technique which entailed making a drawing at the same size as the intended fresco and, placing that drawing onto the arriccio or onto the wet intonaco, the artist would 'pounce' (a little bag filled with charcoal dust) over the previously-made holes in his drawing, thereby creating a type of 'join-the-dots' image, which he subsequently did, to end-up with his newly transferred drawing; if directly onto the wet intonaco, then only the part he was about to work on that day. This is important because, in what's known as buon fresco painting, the intonaco must be damp so that the paint will become one with the plaster; should the painter wish to add details or correct something after the plaster is dry, it is no longer buon (or, true) fresco but rather, a secco, that is, 'when dry'. The problem (with a secco) is, given that the paint is now on the plaster and not part of the plaster, those parts painted a secco tend, over time, to drop off. In fact, many frescos have a secco additions, or rather, had a secco additions! At any rate, the second and related way, a kind of intermediate step, of getting a drawing onto the intonaco, was that of the quadrettatura, or as we say in English, 'squaring-up'; this involves drawing a grid of squares onto a small drawing or sketch - where most problems could be worked out in advance - and then transferring the 'contents' of each square onto a larger grid on a large sheet, or sheets, of paper; this latter is the same size as the intended fresco or part thereof . 

A very large drawing on 19 sheets of paper glued together: A group of Men-at-arms for the Martyrdom of Saint Peter fresco by Michelangelo in the Pauline Chapel in The Vatican. This cartoon (c.1546-1550) is in the Museo e Real Bosco di Capodimonte, Naples (Photo: the author)

This fantastic work, known as a 'cartoon' (cartone in Italian: heavy paper), already discussed in this blog (see Concerning Borrowings), has visible holes along all the major lines - an obvious sign of the use of spolvero -  and we know that it was utilised for a smallish part at the lower left of the large fresco which Michelangelo painted in the Vatican (Pauline) chapel. This is therefore an example of the spolvero technique being used by a major painter in the middle of the 16th century. A variation of this technique, without the charcoal dust, was the use of a stylus to draw over the lines of a cartoon which had been placed on the wet intonaco; the stylus, applied with some pressure, would leave an imprint of the drawing's lines in the wet plaster and the painter would then proceed as normal. Michelangelo himself used this method in at least some parts of the Sistine Ceiling frescos, the imprint of the stylus still clearly visible in the plaster.

Lamentation over the Dead Christ with Two Angels, c. 1447, by Andrea del Castagno (1419-57); detached fresco. 

Cenacolo di Sant'Apollonia, Florence (both this photo and the next by the author) 

The sinopia of the fresco, in the photo above, by Andrea del Castagno; both photos unfortunately not as clear as they might be.

The two works shown here, and the details which follow, all by the painter Andrea del Castagno, demonstrate the incisive power of expression as well as the emotional depth of this wonderful artist 4. What struck me when I first saw these works in person (Andrea's work does appear in general art history books) was the beauty and extreme mastery of his drawing; having studied at art schools (in Melbourne) in the early 1970s, and being painfully aware of my own shortcomings in this regard, these drawings - not to mention the frescos themselves - came as an enormous shock. A close look at the sinopia reveals not only the beauty and even elegance of his line, but also its precision; the lines 'carry' or intimate the form, not just the shape - even where there is little or no shading - similarly to the way they do in Michelangelo's drawings. And the lines we are seeing here are made with a brush! - albeit perhaps on top of a prior charcoal drawing; note especially the angel on the right, his arm and particularly his face, not to mention the torso of Christ.

The two images above show details of the Lamentation over the Dead Christ by Andrea del Castagno, just discussed (again, not the best photos!)

I have included these two photos so that readers might have a better idea of the work under discussion and to show how such paintings look after having been restored. Contemporary restoration of artworks demands that while lacunae may be in-filled with completely reversible paints, 'corrections' and even 'improvements' are absolutely to be avoided - practices unfortunately very common in earlier times. In the lower photo is fairly easily visible a 'frontier' so to speak between the original part of the painting - the upper part - and the work of the restorer: almost the entire lower portion of the sarcophagus and of the decorative border are restorations. But the photos also reveal what the drawing, the sinopia, has become; in some cases (not this one), from a personal point of view, one might occasionally prefer the exquisite sinopia to the finished fresco! 5

A brief reference now to the actual methods used to remove a fresco from its wall; these are two: the stacco and the strappo. The former removes the pigment layer and a good bit of the plaster while the latter removes only the colour layer with a very small amount of plaster (the decision about which to use depends on the condition of the fresco). Both methods involve glueing layers of material, usually canvas, to the front surface, the actual painting, and, once dried, pulling the now glued plaster surface off the wall; it is at this point that any sinopia becomes visible (still on the arriccio underneath). Again in both cases, excess plaster is removed from the 'back' of the intonaco and another canvas is applied there; after this, the canvas on the front is carefully removed and the now-detached fresco is attached to reinforced masonite sheets. At this point, the fresco is ready to be placed back in its original position, usually of course, after a thorough restoration, or to go into a museum, such as has happened with the della Gatta Penitent Saint Jerome above. 

In conclusion, mention might be made here of an altogether more 'brutal' method of getting a fresco off a wall or, better said, removing a fresco; this because in fact, it is the entire section of wall on which the fresco sits which is bodily removed! This also is a very old technique and involves the careful cutting, around the edge of the picture, of the stones or bricks which make-up the wall itself, and through an obviously very laborious and difficult process, moving that part of wall to another location (where it is inserted into another wall). Perhaps the best-known of this type of transfer is that of the great Resurrection fresco of Piero della Francesca in Sansepolcro; originally situated it is thought in another room of the council building, it was removed - with its wall - to its present site, a fact re-confirmed by the most recent restoration.

The Resurrection by Piero della Francesca, 1458 (?), fresco, 225 x 200 cm - here without the painted columns at the sides. Museo Civico, Sansepolcro 

(Photo: by the author, post the recent restoration)

* Sinopia - singular; Sinopie - plural

1 This beautiful sinopia has been discussed previously in this blog's article entitled 'Bits and Pieces'.

2 Fresco painting has been known since ancient times, not only in the West but also in India and China. The best-known early frescos in the West are probably those at Pompei where many are still in situ while others have been moved, together with those from Herculaneum, to the Museo Archeologico Nazionale di Napoli (MANN), a wonderful museum worth the visit to Napoli all on its own. Frescos from various periods however may be seen in many museums throughout Italy.

3 Cennino Cennini, Il libro dell'arte (The Book of Art), written towards the end of the 14th century or in the early 15th, is an invaluable 'recipe book' for contemporary art restorers and historians. It is what is sometimes referred to as a 'libro di bottega', or, 'workshop book': in other words, a workshop manual of recipes and procedures for apprentices working in an artist's studio - at the time, and later, a kind of studio-cum-retail shop. Cennino's advice concerning the painting of frescos, and other things, has been a critical, indispensable source of knowledge of late-medieval workshop practice.

4 For further discussion of Andrea del Castagno, please see the article in this blog entitled 'Reflections on the Writing of Art History'.

5 An excellent discussion (with one reservation) of this topic, in English, is to be found in a catalogue - actually a small book - of an exhibition held at the Metropolitan Museum of Art in New York in 1968 (later at the Rijksmuseum and in London): The Great Age of Fresco - Giotto to Pontormo (various authors). The one problem I found with this explication of the fresco technique was one which is common: that is, that the specific and critical translucent quality of the intonaco is not properly explained. If the intonaco were not translucent, what on earth would be the point of making such beautiful drawings (the sinopie) if the painter then covered them up in such a way that even he could no longer see them? From a technical point of view, this point is manifestly important but, for some reason which escapes me, art historians and others explain the fresco procedure in such a way that the sinopia is basically rendered useless by the application of the intonaco layer!