CHAPTER XIII

THE COLOURS USED BY THE MEDIÆVAL ILLUMINATOR

One can hardly study the illuminated work of the Middle Ages without being interested in the methods employed by the artists of this period. The MSS. still in existence, with colours still fresh and bright, make one curious to know what colours were used to produce this result.

Our knowledge of the colours used in classical times is derived chiefly from Pliny’s “Natural History” and the writings of Vitruvius. Theophrastus, in his work on stones, also adds some description of pigments.

It appears from these writers that the earth colours, such as the ochres and siennas, were well known, as also was the green earth terra verte. Blues and greens were obtained from the ores of copper, one of the most notable being azurite, a blue carbonate of copper. Verdigris was prepared by the action of vinegar on copper. Cinnabar, a native variety of red sulphide of mercury similar to our vermilion, which is the same thing artificially prepared, and orpiment, the native sulphide of arsenic, were also colours used at this period.

A number of white earths were also employed, chalk being the most important. White lead was used, being prepared in practically the same way as the best is to-day. Lakes were made by dyeing chalk or gypsum. Several vegetal dyes were used for this purpose, such as madder, weld, and woad. In addition to these dyes, lakes were prepared from kermes and the celebrated murex. Kermes is a red dye caused by a small insect similar to that of the cochineal insect; it was used for dyeing and for making pigments, both in classical and mediæval times. The murex was a species of shellfish from which was extracted the famous purple dye. This was the dye used for the purple vellum that was used so much in the early period.

The blacks used were carbon-blacks, such as lamp-black, bone-black, or the black prepared from grape husks and vine leaves.

Indigo was undoubtedly in use, and it is highly probable that the red resin known as dragon’s blood was also in use. Pliny, in his “Natural History,” describes the fighting between the elephant and the dragon, and he states that the name cinnabar should be given to the thick matter which issues from the dragon when crushed beneath the weight of the dying elephant, mixed with their blood. It is thought that he may be referring to this pigment, for, in another chapter, he refers to India sending the corrupt blood of her dragons and elephants. There is one colour, which was one of the principal pigments of the Middle Ages, of which no mention is made in the classical period, and that is ultramarine.

It is difficult to be certain as to how the different colours were mixed, but the ink used was prepared from lamp-black mixed with gum and water, and it is probable that the colours were mixed with either gum, glue, or egg.

The Lucca MS. of the eighth century, in the cathedral library at Lucca, contains, amongst other things, a short list of pigments. There is very little difference between the information given here and that given by Pliny. This MS., however, gives the first distinct directions for making artificial vermilion. It is also interesting as giving definite information as to how colours were mixed for working on parchment or vellum, as the following quotation plainly shows: “On wood the colours being mixed with wax, on _skins_ fish-glue being mixed.”

In the twelfth-century MS., the Mappæ Clavicula, the greater part of the Lucca MS. is repeated.

The Schedula Diversarum Artium of Theophilus is also of about the same date, and is a very important MS. It is divided into three books, the first dealing with painting, the second with the manufacture of glass, and the third with metal-work. It is evident that Theophilus, who was a monk in some German monastery, was a worker in metal. However, he collected quite a lot of information on various forms of art work. It is, of course, in the book on painting that the information with regard to colours is found.

In Chapter XXVII. he gives instructions for preparing the gum for mixing with colours. This is described as follows: “Take gum which exudes from the cherry or plum tree, and, cutting it up very small, place it in an earthenware pot, and pour water upon it abundantly and place it in the sun, or in winter upon the coals, until the gum has liquefied; and mix it together with a smooth piece of wood. Then strain it through a cloth, and grind the colours with it and lay them on.”

In Chapter XXXIV., which is entitled “How Colours are Tempered for Books,” he says: “Make a mixture of the clearest gum and water as above, and temper all colours except green and ceruse and minium and carmine. Salt green is worth nothing for books. You will temper Spanish green with pure wine, and if you wish to make shadows, add a little sap of iris or cabbage or leek. You will temper minium and ceruse and carmine with clear of egg. Compose all preparations of colours for a book as above, if you want them for painting figures. All colours are laid on twice in books, at first very thinly, then more thickly; but once for letters.”

Salt green, that is mentioned here, was a mixture of verdigris and subchloride of copper. Spanish green was verdigris, and minium was red lead, while ceruse was white lead. Verdigris is, of course, a notoriously fugitive colour, but while in ordinary water-colour painting it would probably not be safe to use, it would last fairly well in books. Certainly it seems to have done so in the past, if one may judge from the greens in many of the old MSS., which are still brilliant.

Other colours described are those known as “folium” colours. These seem to have been different vegetal dyes.

In Chapter XL. he gives a description of how to prepare ink. This is quite different from the ink of the classical period, which, as mentioned before, was made from lampblack and gum-water. The ink described by Theophilus is more of the nature of our modern writing-ink, being prepared from the bark of thorn-trees, amounting really to an infusion of tannin, with the addition of iron sulphate, popularly known as green vitriol.

There is no mention in this MS. of the preparation of ultramarine.

Following this there are the MSS. that have been translated by Mrs. Merrifield, _viz._, Eraclius, Alcherius, the book of Peter St. Andemar, all included in the MSS. of La Bègue, the Sloane MS., and the Strassburg MS.

The MS. of Eraclius is regarded as not being later than the thirteenth century, the first two books being very early and quoted by Theophilus.

In these MSS. it is plainly stated that the colours were generally mixed with either gum-water or egg. White of egg was often used, but occasionally the yolk. For example, it seems to have been used as a medium for vermilion and orpiment. These MSS. contain a lot of information very similar to that in the MS. of Theophilus.

Lakes were, in the earliest MSS., prepared in a similar way to that used in the classical period, and are described in this manner in the MS. of Eraclius. In the MS. of Jehan le Bègue, however, there are several recipes that have been compiled by him from the MSS. of Alcherius, of the fourteenth century, which are practically the same as the modern method.

The MS. of Le Bègue is also of interest, as it contains a recipe for the preparation of real ultramarine.

Perhaps the most interesting MS. of all is that known as the Book of the Art of Cennino Cennini. This is a most delightful treatise on the methods then in use. Cennino Cennini was an Italian painter and was living in Padua in 1398. The MS. in the Vatican is dated 1437, but this is in all probability merely the date attached by the copyist. It is evident that the colours and methods that he mentions were in use during the fourteenth century.

As this was a period when some of the finest examples of illumination were produced, it is interesting to note the various colours used, so they are given in detail.

The reds mentioned by him are sinopia, cinabrese, cinnabar, minium, amatisto, dragon’s blood, and lake. Sinopia is a similar colour to light red, either native or prepared by roasting yellow ochre. Cinabrese is a mixture of sinopia with chalk. Cinnabar, as mentioned before, is mercuric sulphide, which, when artificially prepared, is termed vermilion. There is hardly any doubt that the variety Cennino was familiar with was the artificial kind, for he remarks that it “is produced by alchemy, performed in an alembic.” Minium is red lead, while amatisto is probably hæmatite. Dragon’s blood, as already referred to, is a resinous colour, and lakes were prepared from various dyes.

The yellow pigments were ochre, giallorino, orpiment, risalgallo, zafferano, and arzica. Giallorino is supposed to have been a native mineral yellow pigment. It is described by Cennino as a volcanic product. Some, however, think this to be similar to the pigment that used to be known as Naples yellow, which was a compound of the oxides of lead and antimony. Risalgallo realgar, or red orpiment, was prepared by gently heating orpiment. Zafferano was saffron, while arzica was a lake prepared from weld, which is wild mignonette.

The greens that he refers to are verde terra, verde azzurro, and verderame. Verde terra is the natural earth known also as terra verte. In all probability verde azzurro was a native copper carbonate, similar to green bice. Verderame was verdigris.

The blues used were azzurro della magna, azzurro oltre marino, and indaco baccadeo. Azzurro della magna was a copper-blue similar to the azurite of the classical period. Azzurro oltre marino was the genuine ultramarine. Cennino’s description of the preparation of this pigment from the _lapis lazuli_ is very similar to the recipes that are given in other MSS. Indaco baccadeo was indigo from Bagdad.

The white pigments were bianco sangiovanni and biacca. Bianco sangiovanni was whiting or chalk, while biacca was white lead.

The blacks were “a soft black stone,” black “made of the young shoots of the vine, which are to be burnt, and when burnt, thrown into water, and quenched, and then ground like other black pigments.” Another black pigment “is made of the shells of almonds, or of peach-stones.” Lampblack was also used.

The colours were mixed with gum arabic or egg.

Cennino also makes mention of the use of the _pezzuole_ colours, or clothlet tints, which were used a great deal in the Middle Ages. These were pieces of linen stained with transparent pigments. When required for use, a small piece was cut off and soaked in water to make a tint of the colour, a little gum being added.

Cennino also treats of tinting parchment with various colours. This was not done, as was the custom in the earlier period, by staining the vellum with a dye, but by washing a colour over it with a large brush.

It may be noted that practically all the permanent colours mentioned in these MSS. are in use to-day. Some of the colours used in the Middle Ages can hardly be recommended to-day. The copper blues, for instance, are not reliable, as impure air is very liable to change them into copper sulphide. Orpiment is an unsafe colour to use, while kermes will fade in a strong light, besides being no longer an article of commerce. Both dragon’s blood and saffron are notoriously fugitive colours.

It is hoped that these few brief notes with regard to the colours used by the mediæval artist may be of interest to the student. If he wishes to study this subject further he is referred to the various works mentioned.