Csornay Boldizsár - Dobos Zsuzsa - Varga Ágota - Zakariás János szerk.: A Szépművészeti Múzeum közleményei 99. (Budapest, 2003)

DÁGI, MARIANNA: 'Tinkers' and 'Patchers': Some Notes on the Ancient Repairs of Greek Vases

repaired vases cylindrical and sunk holes only can be found. The characteristic conical shape of the sunk holes may be the result of the arrowhead bits, while in the case of cylindrical drill holes it cannot be decided so far whether solid rod or core drills were used for their execution.

25 Both drill hole types are still in use nowadays;

26 therefore the shape of the drill holes does not give enough indication of whether it was made in Antiquity or afterwards. Evidently we need other dating bases: the size of the drill hole and the technique of drilling can be assumed to be useful for datation.

27 However, the size of the drill hole can be immediately excluded as a basis for dating. We have a set of data clearly showing that the sizes of Antique drill holes can change from one to eight millimetres and different sized holes can appear on the same vase.

28 Regarding the technique of drilling, two details may be involved: the wall and the edge of the hole. Their examination focuses on the damage caused with modern drills and bits, and on seeing whether the drill holes and the walls are more regular, as made with a modern drill or a steel bit, than those made by Antique tools. But investigating the flaking of the edge of the cylindrical drill holes we can draw conclusions only about the direction of drilling - that is, whether the drilling began from the interior or from the exterior of the vase - but not its age. Moreover, no such result do we have in the case of sunk drill holes, because the edge of the conical part of it does not show any traces of damage. Mechanical drills always make precisely cut and regular holes. But a drill hole with a non-circular shape tells us only whether it was made with a hand or a bow drill and not with a mechanical one.

29 The examination of hole walls may give more reliable hints, because the bits 25 The difference between the two bits can be seen on the rim of the hole. We may assume that the drill hole made with a core drill results in a sharper angle on the edge than one made with a solid bit. To settle this question further examinations are required. 26 Nowadays the sunk hole has two types according to the profile of the sunken part. It can be cylindrical or conical sunk. The ancient examples known to me have sunk holes with conical profile only. 27 The technique of drilling depends largely on the induration of the material to be drilled. The harder the material the more practical is the use of abrasives or lubricants to reduce attrition and thus the heat. Experiments performed on seals are published by Gwinnet - Gorelick 1987, 20-23. To drill pottery no such intermediates are necessary. The fired clay can be carved by means of a knife, for its hardness is rated 4-5 on the Mohs scale. (For comparison: marble is rated 3, limestone 3.5-4, hematite 5.5-6.5, rock crystal 7.) 28 The pieces of the Collection of Greek and Roman Antiquities mended in Antiquity have holes of sizes between 2 and 3.5 mm. See also Elston 1990, 59. The holes of different sizes on one object may indicate that it was mended several times. See Boardman, J., The History of Greek Vase Painting, London 2001, 162. 29 See the following experiment: compare three drilling holes of an arched sherd with slip on one side. One drilling was executed with a palm drill starting on the slipped surface, another with a mechanical drill from the same direction, and the last with a palm drill from the plain side of the sherd. It is noteworthy that the clay is flaked off more heavily on the plain side than on the slipped one. It allows us to assume that the vases under repair were drilled from the exterior, causing less damage there. It is to be noted that the mechanical drill caused less damage on the slipped surface, but considerably more on the plain one than the palm drill. The hole of a mechanical drill is an even, circular straight hole, while the hole of a palm drill is less even and circular, because it is more difficult to hold this kind of drill straight and thus the hole can be deformed.