It has been recognized in glyptic and other studies (for example Ogden, 1982 and Gorelick and Gwinnett, 1992) that considerable advances in engraving technology were made once the bow drill, originally used vertically with a cap stone, had been adapted so that a cutting wheel could be fitted to a spindle mounted between fixed bearings (an arrangement similar to a “horizontal engraving spindle” or a “fixed lapidary lathe”). In some recent publications it has been suggested that this key innovation occurred as early as the fourth millennium B.C. (see for example Nissen, 1977; Collon, 1986; Gorelick and Gwinnett, 1992). In this paper we present some observations which we have made on Mesopotamian cylinder seals; they suggest that the introduction of the wheel occurred considerably later, probably not until the Old Babylonian period in the first half of the second millennium.

The designs engraved in intaglio around the convex sides of cylinder seals have been extensively studied by antiquarians and archaeologists since the end of the eighteenth century (see Collon, 1987). More recently consideration has been given to the techniques used to shape and polish the seals and to drill their perforations. The seals were usually made from natural minerals or stones and some of the major lapidary methods employed in Mesopotamia during the 3000 years or so of cylinder seal production, a time span which stretched from the Chalcolithic period to the Iron Age, have been identified (Gorelick and Gwinnett, 1978 and 1989 etc). Advances in lapidary methods, which allowed harder stones such as hematite and subsequently quartz to be commonly worked for seals during the second millennium, appear to reflect the advantages gained by the availability of emery, a more efficient abrasive material than quartz (Heimpel et al., 1988). Other advantages appear to have been gained by the change from stone-based lapidary techniques to those employing metal (copper alloy) tools (Gwinnett and Gorelick, 1987).