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It is well known that the ancient Grecian artists carried the art of painting to the highest degree of perfection, and that their paintings were admired and sought after by the most eminent and accomplished men of antiquity; and Pliny gives us a catalogue of a great number of first-rate pictures, and a historical account of a vast many celebrated painters of antiquity. In his own time, he says, the art of painting had lost its importance, statues and tablets having came in place of pictures.

Two kinds of colours were employed by the ancients; namely, the florid and the austere. The florid colours, as enumerated by Pliny, were minium, armenium, cinnaberis, chrysocolla, purpurissum, and indicum purpurissum.

The word minium as used by Pliny means red lead; though Dioscorides employs it for bisulphuret of mercury or cinnabar.

Armenium was obviously an ochre, probably of a yellow or orange colour.

Cinnaberis was bisulphuret of mercury, which is known to have a scarlet colour. Dioscorides employs it to denote a vegetable red colour, probably similar to the resin at present called dragon’s blood.

Chrysocolla was a green-coloured paint, and from Pliny’s description of it, could have been nothing else than carbonate of copper or malachite.

Purpurissum was a lake, as is obvious from the account of its formation given by Pliny. The colouring matter is not specified, but from the term used there can be little doubt that it was the liquor from the shellfish that yielded the celebrated purple dye of the Tyrians.

Indicum purpurissum was probably indigo. This might be implied from the account of it given by Pliny.

The austere colours used by the ancient painters were of two kinds, native and artificial. The native were sinopis, rubrica, parætonium, melinum, eretria, auripigmentum. The artificial were, ochra, cerussa usta, sandaracha, sandyx, syricum, atramentum.

Sinopis is the red substance now known by the name of reddle, and used for marking. On that account it is sometimes called red chalk. It was found in Pontus, in the Balearian islands, and in Egypt. The price was three denarii, or 1s. 11¼d. the pound weight. The most famous variety of sinopis was from the isle of Lemnos; it was sold sealed and stamped: hence it was called sphragis. It was employed to adulterate minium. In medicine it was used to appease inflammation, and as an antidote to poison.

Ochre is merely sinopis heated in a covered vessel. The higher the temperature to which it has been exposed the better it is.

Leucophorum is a compound of 6 lbs. sinopis of Pontus, 10 lbs. siris, 2 lbs. melinum, triturated together for thirty days. It was used to make gold adhere to wood.

Rubrica from the name, was probably a red ochre.

Parætonium was a white colour, so called from a place in Egypt, where it was found. It was obtained also in the island of Crete, and in Cyrene. It was said to be a combination of the froth of the sea consolidated with mud. It consisted probably of carbonate of lime. Six pounds of it cost only one denarius.

Melinum was also a white-coloured powder found in Melos and Samos in veins. It was most probably a carbonate of lime.

Eretria was named from the place where it was found. Pliny gives its medical properties, but does not inform us of its colour. It is impossible to say what it was.

Auripigmentum was yellow sulphuret of arsenic. It was probably but little used as a pigment by the ancient painters.

Cerussa usta was red lead.

Sandaracha was red sulphuret of arsenic. The pound of sandaracha cost 5 as.: it was imitated by red lead. Both it and ochra were found in the island Topazos in the Red Sea.

Sandyx was made by torrefying equal parts of true sandaracha and sinopis. It cost half the price of sandaracha. Virgil mistook this pigment for a plant, as is obvious from the following line:

Sponte sua sandix, pascentes vestiet agnos.70

Siricum is made by mixing sinopis and sandyx.

Atramentum was obviously from Pliny’s account of it lamp-black. He mentions ivory-black as an invention of Apelles: it was called elephantinum. There was a native atramentum, which had the colour of sulphur, and got a black colour artificially. It is not unlikely that it contained sulphate of iron, and that it got its black colour from the admixture of some astringent substance.

The ink of the ancients was lamp-black mixed with water, containing gum or glue dissolved in it. Atramentum indicum was the same as our China ink.

The purpurissum was a high-priced pigment. It was made by putting creta argentaria (a species of white clay) into the caldrons containing the ingredients for dying purple. The creta imbibed the purple colour and became purpurissum. The first portion of creta put in constituted the finest and highest-priced pigment. The portions put in afterwards became successively worse, and were, of consequence lower priced. We see, from this description, that it was a lake similar to our modern cochineal lakes.71

That the purpurissum indicum was indigo is obvious from the statement of Pliny, that when thrown upon hot coals it gives out a beautiful purple flame. This constitutes the character of indigo. Its price in Pliny’s time was ten denarii, or six shillings and five-pence halfpenny the Roman pound; which is equivalent to 8s. 7⅓d. the avoirdupois.

Though few or none of the ancient pictures have been preserved, yet several specimens of the colours used by them still remain in Rome and in the ruins of Herculaneum. Among others the fresco paintings, in the baths of Titus, still remain; and as these were made for a Roman emperor, we might expect to find the most beautiful and costly colours employed in them. These paints, and some others, were examined by Sir Humphrey Davy, in 1813, while he was in Rome. From his researches we derive some pretty accurate information respecting the colours employed by the painters of Greece and Rome.

1. Red paints. Three different kinds of red were found in a chamber opened in 1811, in the baths of Titus, namely, a bright orange red, a dull red, and a brown red. The bright orange red was minium, or red lead; the other two were merely two varieties of iron ochres. Another still brighter red was observed on the walls; it proved, on examination, to be vermilion or cinnabar.

2. Yellow paints. All the yellows examined by Davy proved to be iron ochres, sometimes mixed with a little red lead. Orpiment was undoubtedly employed, as is obvious from what Pliny says on the subject: but Davy found no traces of it among the yellow colours which he examined. A very deep yellow, approaching orange, which covered a piece of stucco in the ruins near the monument of Caius Cestius, proved to be protoxide of lead, or massicot, mixed with some red lead. The yellows in the Aldobrandini pictures were all ochres, and so were those in the pictures on the walls of the houses at Pompeii.

3. Blue paints. Different shades of blues are used in the different apartments of the baths of Titus, which are darker or lighter, as they contain more or less carbonate of lime with which the blue pigment had been mixed by the painter. This blue pigment turned out, on examination, to be a frit composed of alkali and silica, fused together with a certain quantity of oxide of copper. This was the colour called χυανος (kyanos) by the Greeks, and cæruleum by the Romans. Vitruvius gives the method of preparing it by heating strongly together sand, carbonate of soda, and filings of copper. Davy found that fifteen parts by weight of anhydrous carbonate of soda, twenty parts of powdered opaque flints, and three parts of copper filings, strongly heated together for two hours, gave a substance exactly similar to the blue pigment of the ancients, and which, when powdered, produced a fine deep blue colour. This cæruleum has the advantage of remaining unaltered even when the painting is exposed to the actions of the air and sun.

There is reason to suspect, from what Vitruvius and Pliny say, that glass rendered blue by means of cobalt constituted the basis of some of the blue pigments of the ancients; but all those examined by Davy consisted of glass tinged blue by copper, without any trace of cobalt whatever.

4. Green paints. All the green paints examined by Davy proved to be carbonates of copper, more or less mixed with carbonate of lime. I have already mentioned that verdigris was known to the ancients. It was no doubt employed by them as a pigment, though it is not probable that the acetic acid would be able to withstand the action of the atmosphere for a couple of thousand years.

5. Purple paints. Davy ascertained that the colouring matter of the ancient purple was combustible. It did not give out the smell of ammonia, at least perceptibly. There is little doubt that it was the purpurissum of the ancients, or a clay coloured by means of the purple of the buccinum employed by the Syrians in the celebrated purple dye.

6. Black and brown paints. The black paints were lamp-black: the browns were some of them ochres and some of them oxides of manganese.

7. White paints. All the ancient white paints examined by Davy were carbonates of lime.72 We know from Pliny that white lead was employed by the ancients as a pigment; but it might probably become altered in its nature by long-continued exposure to the weather.