The pigments used by the Assyrians seem to have derived their tints entirely from minerals.  The opaque white is found to be oxide of tin; the yellow is the antimoniate of lead, or Naples yellow, with a slight admixture of tin; the blue is oxide of copper, without any cobalt; the green is also from copper; the brown is from iron; and the red is a suboxide of copper.  The bricks were slightly baked before being painted; they were then taken from the kiln, painted and enamelled on one side only, the flux and glazes used being composed of silicate of soda aided by oxide of lead; thus prepared, they were again submitted to the action of fire, care being taken to place the painted side upwards, and having been thoroughly baked were then ready for use.

The Assyrian intaglios on stones and gems are commonly of a rude description; but occasionally they exhibit a good deal of delicacy, and sometimes even of grace.  They are cut upon serpentine, jasper, chalcedony, cornelian, agate, sienite, quartz, loadstone, amazon-stone, and lapis-lazuli.  The usual form of the stone is cylindrical; the sides, however, being either slightly convex or slightly concave, most frequently the latter. [PLATE LXXIX., Fig. 3.] The cylinder is always perforated in the direction of its axis.  Besides this ordinary form, a few gems shaped like the Greek—­that is, either round or oval—­have been found:  and numerous impressions from such gems on sealing-clay show that they must have been a tolerably common.  The subjects which occur are mostly the same as those on the sculptures—­warriors pursuing their foes, hunters in full chase, the king slaying a lion, winged bulls before the sacred tree, acts of worship and other religious or mythological scenes. [PLATE LXXXI.  Fig. 1.] There appears to have been a gradual improvement in the workmanship from the earliest period to the time of Sennacherib, when the art culminates.  A cylinder found in the ruins of Sennacherib’s palace at Koyunjik, which is believed with reason to have been his signet, is scarcely surpassed in delicacy of execution by any intaglio of the Greeks. [PLATE LXXXI., Fig. 1.] The design has a good deal of the usual stiffness, though even here something may be said for the ibex or wild-goat which stands upon the lotus flower to the left:  but the special excellence of the gem is in the fineness and minuteness of its execution.  The intaglio is not very deep but all the details are beautifully sharp and distinct, while they are on so small a scale that it requires a magnifying glass to distinguish them.  The material of the cylinder is translucent green felspar, or amazon-stone, one of the hardest substances known to the lapidary.

[Illustration:  PLATE 81]