As has been already indicated, clay was the material mostly used by the Assyrian and Babylonian scribes for the purposes of writing; but stone was also extensively used from the earliest to the latest times. Stone obelisks, colossal statues of bulls and lions, and last but far from least the bas-reliefs which decorated the walls of the royal palaces were generally covered with an inscription, the wedges sometimes measuring as much as two inches. In writing on sculpture the carved figures were completely ignored, the inscription being chiselled regardlessly through every detail of the carving. Stone was however sometimes used solely and exclusively as the material medium for perpetuating a legal agreement, or immortalizing the work of some self-satisfied grandee, and tablets of limestone or alabaster exist in large numbers, good examples of which are those of Rîm-Sin and Sin-Gamil, rulers of the ancient city of Larsa. Boundary-stones or land-marks form another interesting class of inscribed stone objects. The texts refer to land-tenure and property conveyancing, while the upper part of most of these boulder-shaped monuments is sculptured in relief with mythological emblems. They belong almost exclusively to the Kassite period. Sometimes a plan of the field seems to have been chiselled on the stone which marked its boundary. A good example of such a boundary-stone is that of Nebuchadnezzar I, which was discovered at Nippur and is published by W. J. Hinke;[45] a further point of interest about this stone is that it is inscribed with a hymn to En-lil, the god of Nippur.