CHAPTER V
_TECHNICAL PROCESSES_
Nature of clay—Places whence obtained—Hand-made vases—Invention of potter’s wheel—Methods of modelling—Moulded vases and relief-decoration—Baking—Potteries and furnaces—Painted vases and their classification—Black varnish—Methods of painting—Instruments and colours employed—Status of potters in antiquity.
In this chapter we propose to deal with the various technical processes required for the manufacture of painted vases, that being of all the methods of working in clay employed by the Greeks the most important, and thus, as already implied, forming the main branch of our subject. These vases show, in fact, the highest point of perfection to which the ceramic art attained.
In the making of Greek vases we can distinguish four separate stages: (1) Preparation of the clay; (2) Modelling (_a_) on the wheel, (_b_) by hand, or (_c_) from a mould; (3) Baking; (4) Painting, glazing, and other decoration. The last-named is not absolutely essential, _i.e._ a vase, especially one for ordinary daily use, may be considered complete without it. Further, the three first stages are practically the same at all periods of Greek art, whereas the systems of painting and decoration are subject to local variations and chronological development. For the purposes of the present chapter it is sufficient to consider only those vases which have undergone the complete process of manufacture, or what are known for the purposes of study as “Painted Greek Vases.”
1. PREPARATION OF THE CLAY
The paste of these vases is similar to terracotta in its general characteristics, such as the constitution of the mixture of which it is composed; it is in general very delicate, but deeper in tone and finer in texture than that of the terracottas. Brongniart has described it as “tender, easily scratched or cut with a knife, remarkably fine and homogeneous, but of loose texture”[739]; but it would be more accurate to say that it varies in one respect, being sometimes so hard that cutting or scratching has no effect upon it. When broken it exhibits a dull opaque colour, varying from red to yellow and yellow to grey. On being struck it gives forth a dull metallic sound; it is exceedingly porous, and easily allows water to ooze through.
The surface was protected by a fine, thin alkaline glaze, which is semi-transparent, enhancing the colours with which the vase was painted, like the varnish of a picture. It is this glaze which forms the special distinction of the Greek painted vases and renders them, in contradistinction to common pottery or earthenware, the counterpart of the medieval faïences or majolicas, or the finer porcelain of the present day.
As to the chemical composition of the paste, it would seem that hitherto investigations have been confined to vases of Italian origin, but probably those found on Greek soil would yield similar results. The principal ingredients are clay, silicic acid, and iron oxide, with slight admixtures of carbonate of lime and magnesia. The principal results of previous investigations have been tabulated by Blümner,[740] and yield the following average result (chiefly from analyses of vases from Southern Italy):—
Silicic acid 52 to 60 parts. Clay earth 13 to 19 parts. Chalk 5 to 10 parts. Magnesia 1 to 3 parts. Iron oxide 12 to 19 parts.
The largest proportion of clay found in any one vase was 27 parts; there was also one instance given of 24 parts of iron oxide.
The variations in tone of the clay of Greek vases are very marked. The usual colour is an ochre varying from yellowish-white to brownish-red, the mean being a sort of orange. These variations were apparently regulated by the amount of iron oxide employed. It has been noted by Jahn[741] that vases were sometimes moulded “double,” _i.e._ turned on the wheel in two different thicknesses of clay, the finer and ruddier forming the exterior surface for decoration.
The earliest and most primitive Greek vases (including those of the Mycenaean period) in most cases exhibit the natural quality of the clay, ranging from yellow to grey in colour; it is usually coarse and insufficiently baked, and protected by no lustrous glaze. In the early archaic vases, such as those of Melos, Athens, and Rhodes, we observe a pale yellow tone, which is apparently not a glaze, but inherent in the clay.[742] Thenceforward the clay becomes appreciably redder and warmer in tone until the lustrous glaze reaches its perfection in the Attic vases of the fifth century. In the later Italian fabrics again there is a great degeneration, the clay rapidly reverting to a paler hue, especially in the vases of Campania; while in the Etruscan imitations of the third century it is a dull coarse yellow, apparently due to a preponderance of lime. Generally speaking, it may be said that the colour depends on the proportion in which the constituent parts are mixed, a larger proportion of iron oxide producing a redder, a larger proportion of lime a paler hue.
The clay is permeable, allowing water to exude when not glazed, and when moistened emits a strong earthy smell. It is not known how this paste was prepared, for the Greeks have left few or no details of their processes, but it has been conjectured that the clay was fined by pouring it into a series of vats, and constantly decanting the water, so that the last vat held only the finest particles in suspension. The clay was worked up to the right consistency with the hands, and is supposed to have been ground in a mill or trodden out with the feet. Either red or white clay, or a mixture of the two, was preferred by the ancients, according to the nature of the pottery required to be made, as we learn from an interesting passage in the _Geoponica_:—“All kinds of earth are not suited for pottery, but some prefer the reddish variety, others the white; others again blend the two ... but the potter ought personally to assist in the operations and see that the clay is well levigated and not placed on the wheel until he has obtained a clear idea of the probable appearance of the jar after the baking” (vi. 3).
Certain sites enjoyed in antiquity great reputation for their clays. One of the most celebrated was that procured from a mine near the promontory of Cape Kolias,[743] close to Phaleron, from which was produced the paste which gave so much renown to the products of the Athenian Kerameikos. The vases made of it became so fashionable, that Plutarch[744] relates an anecdote of a person who, having swallowed poison, refused to drink the antidote except out of a vessel made of this clay. It seems to have been of a fine quality, but not remarkably warm in tone when submitted to the furnace; ruddle, or red ochre (_rubrica_), being employed to impart to it that rich deep orange glow which distinguishes the finest vases of the best period.[745] Corinth,[746] Knidos, Samos, and various other places famous for their potteries, were provided with fine clays. At Koptos, in Egypt, and in Rhodes, vases were manufactured of an aromatic earth.[747] The extreme lightness of the paste of these vases was remarked by the ancients, and its tenuity is mentioned by Plutarch.[748] That it was an object of ambition to excel in this respect, appears from the two amphorae mentioned by Pliny as preserved in the temple of Erythrae,[749] of extreme lightness and thinness, made by a potter and his pupil when contending which could produce the lightest vase. The thinnest vases which have come down to us are scarcely thicker than pieces of stout paper. Great difference is to be observed in the pastes of vases from widely-separated localities, due either to the composition or to the baking, as has been noted in the case of the terracottas (p. 113).
2. MANUFACTURE OF VASES
The earliest glazed vases were made with the hand, but the wheel was an invention of very remote antiquity, as has been noted in our Introductory Chapter. It is generally supposed that its origin is to be attributed to Egypt. Its introduction into Greece may easily be traced by a study of primitive pottery from any site such as Crete, Cyprus, or Troy, where the distinction between hand-made and wheel-made vessels is clear. Thus in the tombs of Cyprus which belong to the Bronze Age, the earlier finds, dating from about 2500–1500 B.C., are exclusively of hand-made pottery.[750] The latter part of the Bronze Age may be regarded as a transitional period, in which the tombs contain hand-made unglazed painted vases, together with pottery of a much more developed character, with a lustrous yellow glaze, bearing unmistakable evidence of having been turned on a wheel. This pottery appears to be largely imported, as opposed to the local wares, which are still hand-made, and its widespread distribution over the whole of the “Aegean” area marks an important epoch in the history of early ceramics (see