It was not until 1846 that he published a full interpretation of the Persian column of the great Behistun[10] inscription of Darius I. _Babylonian Column._--This successful achievement related, however, only to the Persian column. The mysteries of the Babylonian column had not yet been solved. This task, as will be evident from the complicated nature of the writing mentioned above, was a much more difficult one. The decipherment of the Persian had, however, taught the sound of many cuneiform signs. These sounds were carried over to the Babylonian column as a nucleus of information. Excavations were all the time also bringing new material to light, and a comparison of inscriptions, in many of which the same words were written in different ways, sometimes ideographically and sometimes syllabically, helped on the general stock of knowledge. Rawlinson, Hincks, Jules Oppert, and Fox Talbot were the men who at this stage of the work were still wrestling with the problem. Again Rawlinson was the man to achieve the first distinguished success. In 1851 he published one hundred and twelve lines of the Babylonian portion of the Behistun inscription with transliteration and translation, and accompanied the whole with copious notes in which the principles of the grammar were set forth. A list of the signs and their values was also added. From that day to this the study has steadily gone forward. _Babylonian-Semitic._--The work of Rawlinson and his co-laborers proved that the language of the ancient Babylonians was a Semitic language, closely akin to Hebrew, Aramaic, Arabic, and Ethiopic. Within the next few years after he had found the key to the cuneiform writing, Rawlinson announced that the inscriptions from Babylonia contained material in another and very different language. The researches of later years have fully confirmed this, and scholars call this language Sumerian. The people who spoke it were the inventors of many elements in the civilization of early Babylonia, and for many centuries at the dawn of history divided the country with the Semites. =5. Chronology.=--The materials for constructing the chronology of Babylonian and Assyrian history are as follows: (1) Claudius Ptolemy, an Egyptian astronomer who flourished in the second century A. D., made a list of the kings of Egypt, Persia, and Babylonia back to the accession of the Babylonian king, Nabonassar, in 747 B. C. This list was compiled as an astronomical aid, and is very accurate.