2 SEAL CYLINDERS OF WESTERN ASIA. 
to them. In figs. 1, 1a, we have such an asphalt stopper to a jar, impressed with 
three cylinders, and in fig. 2 a pat of clay, with mark of the string on the back side, 
impressed with cone seals. But the main use of the seal was to authenticate written 
documents, letters, and bills of sale, or receipts for goods or money. For such 
documents we know that clay was used in Babylonia, no other material being so 
convenient and enduring. In fig. 3 we have such a sealed tablet, what is called a 
case tablet, of the period of Gudea, perhaps 2500 B.C. In Egypt clay was seldom 
in use, apparently, for writing, as the Egyptians at an early period learned to 
manufacture papyrus. The papyrus plant does not grow in Babylonia, and, in- 
deed, is not found in Egypt at present, except far up the Nile. Parchment might 
seem to have been a more natural substitute for clay in a country where sheep 
and goats were so plentiful, but we have no evidence that it was known. Indeed 
clay was much cheaper and suffered no deterioration in the wet winters, if properly 
burned. 

Very many of the early. Babylonian cylinders, though probably not the very 
earliest, were more or less concave on the surface, as in fig. 4, that is, they approached 
the shape of a shallow spool. The probable reason for this is that the tablet 
itself was usually convex on its surface, and the cylinder was made concave to fit 
it. The usual tablet was naturally molded in the shape of an ordinary cake of 
soap, with no square edges. At a later time tablets, usually larger ones, were nearly 
flat on the two faces, with square sides and ends. For these a perfectly cylindrical 
seal (fig. 5) would be more convenient, and these came into common use. Indeed, 
only such a perfect cylinder could be used on any material for writing other than 
clay. Still later the cylindrical seal had convex ends, as in fig. 6. In the later 
Persian period the cylinder itself became convex, or even somewhat barrel-shaped 
(fig. 7), and might, if small enough, be set in a ring (fig. 8). But in the case of the 
convex cylinder only a small device was usually engraved on the center surface; 
and, indeed, it may be that the seal had come to be little more than an amulet. 
By this time the cone seal, with a somewhat convex surface at the bottom (figs. 9, 
10), was in common use. It was not always a cone, but quite as frequently the 
section would be approximately a parallelogram with truncated angles. It has 
been suggested by Mr. Boscawen (‘‘The First of Empires,” p. 345) that the cone 
seal was a miniature matsebah, or sacrificial column, worn as an amulet, but I do 
