Another unique object is a clay model of an ox-hoof (Brit. Mus. No. R. 620), inscribed with forecasts. A somewhat similar object is found in a clay model of a sheep’s liver, also preserved in the British Museum (No. 92,668); the inscription which it bears is magical in character, and the object was probably used for divination purposes. Other tablets, though not being moulded in the form of a sheep’s liver, bear the incised outlines of different parts of the liver. Hepatoscopy, or the practice of deriving omens from the shape, size, or condition of the liver, was one of the most popular forms of magic among the Babylonians and Assyrians. Plans of cities seem to have sometimes been drawn on clay tablets, a good example of which is afforded by a tablet discovered at Nippur, and incised with a plan of that city, a plan which in spite of its antiquity seems to have helped the work of the excavators in no small degree. Another example is the British Museum fragment (No. 35385), on which a plan of part of the city of Babylon is still to be seen. Sometimes the plan was merely that of an estate (cf. Brit. Mus. No. 31483), but in one instance at all events, the world itself is the subject (Brit. Mus. No. 92687), the most interesting feature of which from the geographical point of view is the world-encircling ocean—the Babylonians believing the earth to be surrounded by and apparently supported on water: the earth itself was supposed to resemble an inverted saucer in shape, while the heavens bore the same shape, the only difference being that they were obviously more extensive, and the lower edges rested on the earth itself, while the edge of the earth rested upon the ocean. Sometimes amulets were made of clay, a good example of which is Brit. Mus. No. 85-4-8, 1; it is shaped like a cylinder-seal, and is inscribed with an incantation for Shamash-Killâni. Other inscribed clay objects are those known as astrolabæ or instruments for making astrological calculations. [Illustration: FIG. 3.] [Illustration: FIG. 4. (Brit. Mus., 103040.)] [Illustration: FIG. 5. (Brit. Mus., 91102.)]