 Rawlinson remained at home for two years, published in 1851 his memoir on the Behistun inscription, and was promoted to the rank of lieutenant-colonel.He disposed of his valuable collection of Babylonian, Sabaean, and Sassanian antiquities to the trustees of the British Museum, who also made him a considerable grant to enable him to carry on the Assyrian and Babylonian excavations initiated by Layard.During 1851 he returned to Baghdad.