The Craft of Athenian Pottery / An Investigation of the Technique of Black-Figured and Red-Figured Athenian Vases

Number of firings.

Was Athenian pottery once or twice fired?[14] That is, was it decorated in leather-hard or in biscuit condition? This has been one of the most debated questions in Greek ceramics. Archaeologists often assume offhand a number of firings,[15] but without stating any evidence or squarely facing the problems involved. Briefly, the arguments for and against are as follows. As is well known, a large proportion of red-figured vases of good period show a preliminary, colorless sketch for the design traced with a blunt[16] instrument directly on the clay (cf. figs. 43-44). The smooth grooves of this sketch show beyond doubt that the sketch was made while the clay was in leather-hard condition, that is, before firing. If the vase had been fired, even at a low temperature, the sketch would have had to be scratched in with a sharp tool, and would have left a ragged, not a smooth line.[17] Now it is not a natural procedure for an artist to make a rough sketch for his design, and then to leave his vase to be fired before completing his work. Furthermore, an examination of the incised lines on the black-figured vases—which clearly go over the black glaze—shows also that these lines must have been made while the clay was still leather hard. The ragged edge of the glaze along the incisions has sometimes been thought to indicate that they were made after firing. But just this effect is produced by cutting through dry glaze on unfired clay; and it would have been very difficult to attain the required delicacy, swing, and smoothness by incision into hard, fired clay. Any one who will try the experiment will soon become convinced of this.[18] So that, for the black-figured period at least, this evidence points to a once-fired pottery.

On the other hand, it might be urged that if we assume that the decoration was executed in leather-hard condition, the vase painters whom we see depicted on Greek vases should be handling their pots with considerable care, and that this is hardly conveyed in the representations. On the Boston fragment, for instance, the painter is holding a kylix by its slender foot without any apparent fear of breaking it (fig. 67). And whoever painted the scene knew what he was doing, for he was in the act of decorating such a kylix himself. However, if the clay used by the Athenians was of a tough variety,[19] this would, I have been told by potters, be a perfectly possible procedure; and experiments made with imported Athenian clay[20] bore this out to an astonishing degree. Vases made of this clay could be handled quite freely in leather-hard condition. So that if the Athenian potter of the fifth century used similar clay to that of his present-day descendant, his handling of these pots on the vase paintings would be perfectly justified in the leather-hard state.

There is, moreover, evidence which seems to settle this question beyond dispute. On a number of the Athenian vases there are dents such as can only have occurred while the vase was still in a leather-hard state. The mark of the object contact with which caused the dent is invariably over the black glaze (cf. fig. 45), showing clearly that the glaze must have been applied in leather-hard condition.[21] In some cases we find still adhering in the dents a little burnt clay, apparently from another vase contact with which caused the accident. Here it is probable that the accident was caused not while the vase was leather hard, but when red hot in the kiln, at least in those instances, as in the black-figured amphora in the Metropolitan Museum[22] (fig. 46), where the glaze shows a rough fracture due to the separation of the two pieces which had stuck together; for this fractured edge would have become fused and smooth upon subsequent firing.[23]

The fragments of unfinished vases which have been found from time to time[24] have been used as evidence to prove several glaze fires; for they show fired vases at a definite stage in the glazing, the outlines and inner markings painted, but the background not yet filled in. Must we, then, suppose that it was the regular practice—at least in the later red-figured period to which all the unfinished pieces belong—to fire before and after the painting of the background? It is difficult to see what would be gained by the process. If the pottery were fired before any decoration was applied, there would be the advantage of safer handling of the ware; but to have an extra firing with the decoration more than half completed gives no apparent gain and there is the distinct disadvantage of the extra expense of firing.

The unfinished kylix in the collection of the Metropolitan Museum may shed light on this problem (fig. 47). It is not so fragmentary as the pieces in the other museums, being complete except for portions of the rim. The foot is very roughly turned (fig. 48), very different from the average kylix foot, as if it had not been worth while to spend much time on this product. The decoration itself is also quite cursory. This suggests that the piece was merely a “test,” such as potters use often nowadays for making trials of their clay body, or their glaze, or their kiln. The kylix is, as a matter of fact, too soft fired, and the glaze has turned reddish in parts. May we be permitted the guess that this was a trial to test out a new kiln? It is only a possibility and there are many others. The important point is that the evidence of the unfinished fragments does not make it necessary to assume more than one glaze firing.

The probability, therefore, is that Athenian pottery is once fired,[25] all ornamentation—both glaze and accessory colors[26]—being applied while the vase was in leather-hard condition; for in the case of the accessory colors also there would have been no advantage in an additional firing.

Injuries in the firing.

The action of the fire on the potter’s products was apparently as much an open question in Greek times as it is now. Practical experience must have gone a long way then as today; but full control could not be achieved. In forming an estimate of what proportion of the pottery was spoiled in the kiln we must remember that in our museums we are apt to encounter the survival of the fittest—what the potter considered worth preserving, what the Greek client deemed adequate to his need, and what the modern museum curator considers good enough for exhibition. But even in this selection we meet with a number of kiln mishaps, which apparently were so common that they were hardly noticed. When our eyes have become trained to observe such things, we shall note that in any collection of Greek vases there are many cases of warping and sagging, especially in the overhanging lips of the hydriai and amphorai.[27] There are many cracks and dents,[28] many faults in the glaze. A very conspicuous fault is the change of the clay from a pink to a grayish color.[29] Archaeologists often explain this as due to over-firing.[30] The real reason is not that the temperature has been too high, but that the clay has been subjected in the kiln or in the funeral pyre, to fumes the carbon of which has been absorbed by the clay. In other words, there was either reduction and the red ferric oxide in the clay has been changed to black ferrous oxide (cf. pp. 30 f.), or the clay has absorbed the black carbon physically. When controlled, this change is very useful to the potter for obtaining certain effects. Thus bucchero pottery is simply red clay fired under completely reducing conditions; and in the Vasiliki mottled ware some carbonaceous pigment like tar was probably placed on the spots which were intended to be black, whereupon the carbon would be absorbed by the clay and the iron reduced.[31]

The commonest injury to the glaze in the fire is its change into a brilliant red instead of the intended black. This can be observed on many vases, sometimes as a large spot (cf. fig. 49), other times as a less clearly defined variegation.[32] The cause was irregularity of fire, a jet of air passing through the kiln coming in contact with parts of the vases. In other words, there was an excess of oxygen (or the reverse of reduction) which turned the black ferrous oxide of the glaze into red ferric oxide.[33]

Such red spots caused by jets of air coming in contact with the vases must not be confused with the very similar red spots which are due to the wearing off of the black glaze and the exposure underneath it of the ochre-tinted clay (cf. p. 58). Examination with a magnifying glass will show the difference: in one case the red is part of and level with the black glaze, in the other it is on a layer beneath the black glaze; in the former case the red will not come off when rubbed, in the latter it will.

GLAZING

Besides shaping and firing a vase, a potter must understand the art of glazing, to many the most alluring part of the craft; this comprises both the preparation of the glaze and its application to the pot. A glaze is a chemical compound, known as a silicate, which upon firing becomes a glassy substance. It has three chief ingredients: (1) an oxide of lead, of lime, of alkali, etc., which forms the foundation of the glaze; (2) alumina and boron oxide, which regulate the behavior of the glaze in the fire; and (3) silica, which controls the fitting of the glaze to the body. Modern glazes are divided into two chief categories: lead glazes and leadless glazes. Of these the former are by far the more numerous; but alkaline glazes, tin enamels, etc., are also used, especially in studio potteries.

In the preparation of a glaze the ingredients have first to be weighed out carefully in the required proportions; the mixture has then to be ground with water and sieved; and when the right thickness is attained (usually about the consistency of cream), the glaze is applied to the vase, which should first be soaked in water to saturation to prevent too rapid absorption. Gum tragacanth is used as a binder to make the glaze stick.

The glaze can be applied in various ways—by dipping (fig. 50), by pouring (fig. 51), by the use of the brush (fig. 52), or by spraying (fig. 53), the method depending chiefly on the individual choice of the potter. To apply a glaze properly to the clay body is a great art, and upon it, as much as on the preparation of the glaze, final success depends. The glaze mixtures when applied are whitish or grayish; it is only after firing that they assume the wonderful range of colors which delight us so much today.

The Athenian potter had no ambition to produce brilliant color effects in glazing. He was content with the one variety which he had brought to perfection—a thin, luminous glaze of a deep, velvety black color and of astonishing durability. After generations of experiments we cannot yet say that we can successfully imitate it. Its composition is, however, no longer a secret. It has been shown by analysis and synthesis that the chief component parts of the glaze are an alkali (potash or soda), a clay (which would contain some silica such as flint naturally), and ferrous oxide.[34] The exact proportion of these parts, and above all the manipulation of the glaze are still unknown. At least, nothing completely corresponding to the Greek glaze has as yet been produced, though Mr. Tonks[35] and especially Mr. Binns[36] have come very near it. Whether the secret lies in the proportion, in the medium used for binder,[37] or in some undiscovered element one cannot tell. It is only certain that when the discovery is made, as doubtless it must be, it will be of great import both to archaeologists and to modern potters.

The glaze was, as I have endeavored to show (cf. pp. 37 ff.), applied to the vase in leather-hard condition. At that stage the clay still contains enough water to prevent too rapid absorption, and the glaze, therefore, runs in an easy, flowing manner.[38] To carry out his work the painter could take his time, for, as we have seen (cf. p. 16), a vase can be kept leather hard for an indefinite period by the simple device of placing it in a damp box, that is, an air-tight case with a pan of water at the bottom.[39]

How did the Greek painter apply the glaze to his pottery? We know that on the broader surfaces the brush was used, for brush marks are clearly visible in many cases.[40] When possible the backgrounds and horizontal bands were painted while the piece was rotating on the wheel; where a panel had to be reserved, the irregularity of free-hand brush work can readily be observed (fig. 54). For the “flat” glaze lines, in both the figured scenes and the ornamental motives, smaller brushes were employed. But what was the instrument which produced the famous “relief” lines, that is, those fine lines which stand out perceptibly from the surface and which were used for the contours and inner markings of the figures during the best red-figured period (fig. 55)? The quality of these lines has been justly admired by all who have studied them and it has been thought that the instrument used had much to do with the result.[41] After a number of experiments with fine brushes, single bristles, reeds, feathers, pens, etc., I have come to the conclusion that it is of little avail to discuss the instrument used before we can employ in our experiments a glaze identical with the Greek. For to get the wonderful flow of the Greek line, the glaze must run much more easily than any imitation black glaze which we have so far produced. The groove which runs down the middle of the relief lines hardly affords a clue; for slight pressure of any instrument seems to produce such a result.

RED OCHRE WASH

In three statements of ancient writers the addition of red ochre to Athenian pottery is referred to.[42] In Pliny, Natural History, XXXV, 152, we read: Boutades inventum est rubricam addere aut ex rubra creta fingere, “Boutades first added red ochre, or made pottery of red clay.” Isidorus, Etymologiae, XX, iv, 3, speaks of pottery vases having been first invented at Samos and then adds: Postea inventum et rubricam addere et ex rubra creta fingere, “a later invention was to add red ochre and to make pottery of red clay.” Suidas in his lexicon, where he describes Cape Kolias as a place in Attica where pottery is made, says that the clay from that region is the best, and adds: ὥστε καὶ βάπτεσθαι ὑπὸ τῆς μίλτου, “so that it is also dyed with red ochre.”

Archaeologists have assumed that this red ochre was mixed with the clay and that to it was due the deeper color of Athenian ware as compared, for instance, with the geometric. Thus in practically all our books on vases the preparation of the clay for the manufacture of Athenian vases is described somewhat as follows: “The clay having been thoroughly purified and washed, was then kneaded and brought to a consistency suitable for shaping it on the wheel. It was at this stage that other substances, chiefly a red earth (ochre = μίλτος), were worked in with the clay to deepen the color.” First of all, it should be noted that if ochre is to be added to the clay it must be done long before the kneading stage, otherwise the red ochre will of course not mix evenly. The best time would be when the clay is dry, so that a definite proportion could be weighed out. But that is too obvious to need discussion. The question is, Does the addition of red ochre materially change the color of the clay? It may be interesting in this connection to record my experience in the matter. About three years ago I was asked to speak at a convention of modern potters meeting at the Metropolitan Museum of Art, on the subject of Greek vases. I thought that these potters would probably be specially interested in the technical side of Greek ceramics, and with the courage of ignorance I described in detail our theories regarding the manufacture of Greek pottery. It was the questions which the potters asked me afterwards which convinced me that it was time I went to a pottery school. One of my statements which aroused considerable interest was this theory that red ochre was added as an ingredient to deepen the color of red clay. Several men came to me after the talk and said, “I don’t see why the Greeks did that; for by just slightly raising the temperature they could easily have deepened the color.” I had no answer then, but when I went to the pottery school I thought I should take nothing for granted, but convince myself by making my own experiments. So I made some tests, adding certain percentages of ochre to see how it would affect the color. Apparently the ochre had little effect, and the pieces with and without ochre were about equally pink when they came out of the kiln. I then burned some pieces without any ochre to a little higher temperature and the red was considerably deepened. I was quite convinced then that the ochre added as an ingredient to the clay would not have the desired result; besides, if we needed further proof we might remember that analyses made of Athenian clay have shown no trace of ochre.[43]

What, then, do Pliny and Suidas mean when they speak of the addition of red ochre to Athenian pottery? A number of archaeologists have observed from time to time that Athenian vases, especially of the late red-figured period, show traces of a reddish pigment applied over the surface. Reichhold in his technical description of vases in Furtwängler und Reichhold, Griechische Vasenmalerei, frequently refers to it as “rötliche Lasur.”[44] Pottier ascribed it to a sort of varnish or lustre applied over the surface of the decorated, fired vase which on decomposition precipitated into a red deposit.[45] Walters thought that red ochre was rubbed on certain parts of the vase which had remained too pale after baking.[46] A detailed examination of the vases in many European and American museums convinced me that the use of this red pigment was quite general throughout the red-figured period, and to a limited extent in the black-figured period. On a few vases it appears in excellent preservation.[47] The majority of red-figured vases of all periods[48] and a few of the black-figured vases[49] show traces of it. When it is not otherwise visible, it can often be detected in the slight depressions of the preliminary sketch, or under the handles, or on the under side of the foot. As the color comes off when rubbed with a damp cloth, it is not surprising that it is not better preserved, after the extensive cleaning that most museum specimens have undergone. But the many traces which are still preserved can only be satisfactorily explained by assuming that it was the general practice—at least in the red-figured period—to apply a red pigment over the whole surface of the vase.

In the light of this experience let us again examine what Pliny and Suidas say. Pliny’s statement is sufficiently vague to make any interpretation possible; but Suidas’ use of the word βάπτεσθαι, “to be dipped,” is illuminating. The clay could not have been “dipped” in a powdery or liquid state, the only way of having the ochre become an actual ingredient in the clay. The term βάπτεσθαι implies that the clay must have become a solid vase, in which case the ochre was applied only on its surface. Indeed Athenaeus (480 E) uses the term βάπτεσθαι to signify the “glazing” or “silvering” of earthen vessels. So that literary testimony seems to agree with the evidence of the vases themselves that the ochre was applied on the surface. At what stage, then, was this ochre added? Was it before or after the black glaze? Careful examination has shown that it was previous to the glazing. When the black glaze is chipped off it generally takes the surface too, so that instances of the red ochre showing underneath are not numerous; but there are nevertheless a number of undoubted examples.[50] An especially convincing instance is on an amphora in the Metropolitan Museum in which a diluted black glaze line goes clearly over traces of the red lift in a preliminary sketch line (fig. 56). Furthermore, in many cases the glaze on the background surfaces has disintegrated and shows the red ochre beneath.[51]

Since the black glaze was probably applied to the leather-hard clay, the ochre wash must also have been added in that state. The leather-hard vase might have been dipped in an ochre solution or the ochre applied with a brush or rubbed into the surface as a powder. In order to make it adhere properly to the clay actual experiments have shown that by far the best results are obtained by giving the surface a good polish after the application of the ochre. The ochre is thereby actually incorporated with the clay and forms a good firm surface. If not so polished, it is powdery after firing and comes off easily.

Experiments further showed that (1) red ochre applied in this manner on the red clay in leather-hard condition produced an effect identical with the red “wash” observable on the Athenian vases; (2) preliminary sketch lines engraved lightly with a blunt tool did not remove the ochre; (3) the ochre in no way interfered with the adhesion of the black glaze over it; (4) the ochre came off only a little at a time even when rubbed hard while wet. It is therefore only during the long processes of wear and time that the red ochre application has worn off. But even when it has entirely disappeared, it has stained the clay a deeper color—namely, the orangey hues which we see now; for the actual color of the clay is lighter and pinker, as any fracture will show.[52]

Originally, however, we learn from our investigation, the red-figured Athenian vases had an even deeper and richer tint than they have now—approaching more nearly the color of copper. The general effect, therefore, must have been considerably more vivid than it is today, and to some this thought may not at first appeal. But we should remember that we are discovering also in other fields that the Greeks loved bright, intense color, not the faded tints that so many of their works present today.

WERE ATHENIAN VASES MADE FOR EVERY-DAY USE?

The theory has often been advanced that the painted black-figured and red-figured vases were made for decoration and for votive and funeral purposes, but not for actual use. Percy Gardner in his Grammar of Greek Art (p. 160) holds this view and gives as his reason that the painted vases were too fragile to be easily handled and too porous to contain liquid. Reichhold in Furtwängler und Reichhold, Griechische Vasenmalerei, Text, I, p. 82, and Skizzenbuch griechischer Meister, p. 10, is of the same opinion, and bases his assumption on the fact that a number of the vases show ancient rivet marks and could not therefore have served any practical purpose in such a condition; also that no ancient vases show signs of wear, which would have been unavoidable if they had been in daily use. Does our investigation of the technique of Athenian vases help to settle this question? Let us look first at the case in its broader aspects.

Nobody can work long with Greek vases or other forms of Greek industrial art without being impressed with the wonderful combination of beauty and practical utility which these objects show. The Greek vases are not only finely proportioned, but each one is admirably adapted to its purpose. We need only try pouring from an oinochoë to see how easily the liquid flows without any danger of spilling; or from a lekythos to see how the oil trickles through the narrow neck, drop by drop, or in a very thin stream, just right for cooking or the making of salad dressing. We need only drink from a kylix to realize how, contrary to expectations, it is an easy and delightful process—the little curve of the rim preventing the liquid from spilling down one’s cheeks.[53] We need only closely observe the handles of Greek vases to see how their positions, their curves, and above all their extraordinary solidity render them eminently practical. Moreover, the study of a hundred little details, the forms of the knobs on pyxides, the projections for holding the lids in place, the outward or inward curves of the lips, the substantial feet, all combine to form overpowering evidence that these vases were designed for actual use. It is only in isolated instances, such as the loutrophoroi which have no bottoms or the white lekythoi which have no connection between the neck and body, that this rule does not hold good. Such vases, however, belong to clearly defined classes evidently made as votive offerings or as tomb furniture.

That the bulk of vases were made for votive purposes, there is no real evidence. Among the many sixth- and fifth-century inscriptions recording such offerings there are few relating to pottery vases. Nor is it conceivable that these vases were purely ornamental. We know that private houses in Athens were at that period excessively simple, consisting mostly of a courtyard and a few rooms opening on it, so that it is not likely that people surrounded themselves with a lot of useless ornaments; nor can we believe that in a period which, at least in the sixth century, was still one of strenuous endeavor, these vases were exported to all parts of the world merely as decorative bric-à-brac. Everything we know of Greek life at that time points against such an assumption. Moreover, if the Greeks had such decorations in their homes we should expect to see, depicted in the vase paintings, cabinets or shelves with vases displayed on them; instead, when vases are shown, they are invariably in actual use, or hanging on a nail on the wall, ready for immediate service.[54]

There is another consideration. Even if, from our modern point of view, we may hesitate to believe that a beautiful cup of Euphronios was used merely as a drinking vessel, where are we to draw the line? Any one who has worked in a museum or has excavated on fifth-century sites knows that besides the selected specimens exhibited in museum cases there are a large number of inferior examples, hastily decorated, which could hardly have been displayed as ornaments, but which are open to the same objections raised against the vases of better workmanship.

And now let us examine these objections. First, the vases are supposed to be too porous to contain liquid. The fineness of the clay, the polish which was imparted to it, and perhaps the application of the ochre tended to reduce this porosity somewhat. In the course of time the deposit left by wine and oil would still further close the pores. In any case, experiments show that Athenian vases do hold liquids without any difficulty. The unglazed portions become damp, and a damp mark is left on the table if the foot is not glazed; but in the days before highly polished furniture there was no strong objection to that, and there was on the other hand a very real advantage. For it allows a certain amount of evaporation which would tend to cool the liquid—a very desirable thing in a warm climate without a regulated ice supply. Any one who has tried the experiment of keeping water in an unglazed jar in a warm room has found that the evaporation keeps it delightfully cool. In southern Europe today liquids are kept in that manner during the summer. We must also remember that a large number of the early wares from the Bronze Age down, as well as the commoner wares at all times, are either wholly unglazed or have unglazed portions. And surely nobody wants to contend that these vases were not manufactured for use.

The objection that Athenian pottery is fragile is easily disposed of. Actual handling of the vases will show that they are anything but fragile, in fact that they are remarkably strong. All those portions which would get special wear, such as handles and rims, are almost always stoutly made, more so than much of the china and earthenware and glass we use today. Occasionally, of course, we get a very thin and delicate example; and that would have to be handled with special care.

Then, as regards the question of wear. Terracotta is, as a matter of fact, one of the most indestructible materials we have, and especially so when glazed. Glazed earthenware, consequently, even though in constant use shows little trace of wear. What little we should expect, a close inspection of Athenian vases will reveal. The black glaze, even when perfectly preserved on the exterior, is much worn on the interior of stamnoi or kraters (cf. fig. 57), where the liquid came in constant contact with the glaze, and the unglazed interiors of amphorai and hydriai are certainly not perfectly fresh and unused looking. It is also noteworthy that finely and poorly decorated vases are in the same condition in this respect. A comparison with the Corean pottery of the Korai period, 935-1392 A.D.,[55] which is known to have been made to serve merely as tomb furniture, is helpful. The fresh and clean insides of these vases offer a very different appearance from that of the discolored interiors of Greek amphorai and hydriai—a clear proof that the Athenian ware did not serve the same unutilitarian purpose as the Corean.

Lastly, regarding the argument about riveted vases, it is surely natural now and then, instead of throwing away a broken pot, to have it put together and make the best of it in its mended state. We do the same thing nowadays. At all events, the vase could still have been used to contain dry materials. Such Athenian vases with ancient rivet marks are in any case infrequent, and do not compare in number with the broken vases which have not been mended.

Such considerations should once for all explode the theory that Athenian vases were not actually used; so that we can think of them, in the way that appeals to our imagination, as serving in the daily life of the Athenians and as adding to the enjoyment of that life, both by their beauty and by their usefulness.