ABOUT 170 years ago it became known in Europe that there are, on the Upper Yenisei, inscriptions on stone monuments which are written in some unknown language, and are relics of an unknown population. Various hypotheses were made as to the origin of these inscriptions; but it was only in 1893 that the Copenhagen Professor, Wilhelm Tomsen, succeeded in deciphering them.2 Although Prof. Tomsen attributes the discovery of these inscriptions to Heikel and Dr. Radloff, who visited the spot—the former in 1890–1891, and the latter in 1891—they were discovered in reality by the late N. M. Yadrintseff, who was sent out in 1889 by the Irkutsk Geographical Society for a journey to Mongolia.3 Heikel's collection was luxuriously edited by the Finnish-Ougrian Society,4 and the collection of reproductions made by MM. Radloff and Yadrintseff was published by the Russian Academy of Sciences.5 However, neither of these three explorers succeeded in reading the inscriptions, and it was only Prof. Tomsen who, taking advantage of the names of rulers, which were written in Chinese characters, and stood by the runic inscriptions, found the cue for reading the mysterious writings. It became thus known that the inscriptions belonged to a Turkish stem which formerly inhabited the upper parts of the Yenisei and the Orkhon. The cue having been discovered, Prof. Radloff set at once to decipher and to translate the inscriptions—a task which involved very great difficulties at the outset, as the vowels were not written in this alphabet; but with all that, Dr. Radloff succeeded in finding out the meaning of the inscriptions and in translating them, and his researches are now embodied in a work issued by the Russian Academy of Sciences.6 In this work Dr. Radloff analyses, first, the alphabet of the old Turkish monuments, and, next, the Chinese monuments on Lake Kosho-tsaidam; he then gives an eighty-page long list of words; the translation of the Chinese Kosho-tsaidam inscriptions, by Prof. Vasilieff; and the translations of the inscriptions found in different places of Mongolia and on the Yenisei, on both Chinese and Russian territory, followed by a study on the morphology of the old Turkish dialect. Thirty inscriptions in all have been deciphered; they are written phonetically, in vertical columns following each other from the right to the left. The letters are angular; they contain only four vowels and thirty-four consonants—different consonants being used in the words which contain guttural vowels, and in those words which have palatal vowels.