Here he obtained the confidence of certain Parsee priests, who permitted him access to their sacred books, and through whose assistance he acquired sufficient knowledge of the language in which they were written, to enable him to translate the Zend-Avesta. Returning to Paris in 1762, with over a hundred precious manuscripts, he obtained a small post in the royal library, where he spent the next nine years in the preparation of his copies of the original texts of the Zend-Avesta, translating these for publication. In 1771 the work was completed and he had the satisfaction of placing in the Royal Library of Paris the first authentic version of the Zend-Avesta and the first translation that had ever appeared in any European language. As before stated, many scholars of the time were not prepared for the work, denying its authenticity and proclaiming it an audacious forgery. Under this cloud, the intrepid author of this work, conscious of the importance of his contribution to learning, undaunted by the fate which so long delayed the just recognition of his labors, passed the remainder of his days in cheerful resignation. He lived to congratulate Grotefend upon his achievements in the decipherment of cuneiform and died shortly after, in 1808, at the advanced age of seventy-seven. Twenty years later, the honors due his name came through the researches of the illustrious scholars, Rask and Burnouf, who proved this great work of Anquetil Duperron to be a genuine if not correct translation of the Zend-Avesta, as obtained through the sacred books of the Parsees. It was by a study of this translation that the key to the ancient Persian language was obtained and has since served an important use in the study of Zend[5] philology. Notwithstanding its value, this translation of the Zend-Avesta was by no means perfect. The faulty teachings of the Parsee priests led the author into occasional errors which obstructed the progress of later scholars who depended too closely upon it for results. Little by little, however, from the work of Sir Henry Rawlinson on the Behistun inscriptions, thro’ the researches of Burnouf in the original Zend manuscripts; again from testimony furnished by other distinguished scholars, from coins and other inscriptions, and still again by a comparative study of Sanscrit, modern Persian and Arabic, all the letters of the old Persian cuneiform have been obtained, until now it is as easily and distinctly read as Greek or Hebrew. It is impossible, within these limits, to follow the steps by which these important results were obtained. The methods employed in such researches are often only intelligible to philologists themselves. In this special study, the epigraphic materials examined included not only cuneiform signs, but characters representing the fully developed alphabets of later periods, alphabets which had superseded the cuneiform as systems of writing, though expressing the ancient speech of Persia.