This long period of Ottoman peace and, indeed, stagnation is typically characterized by historians as an era of failed reforms. In the latter part of this period there were educational and technological reforms, including the establishment of higher education institutions such as the Istanbul Technical University. Ottoman science and technology had been highly regarded in medieval times, as a result of Ottoman scholars' synthesis of classical learning with Islamic philosophy and mathematics, and knowledge of such Chinese advances in technology as gunpowder and the magnetic compass. By this period, though, the influences had become regressive and conservative. In 1734, when an artillery school was established with French teachers in order to impart Western-style artillery methods, the Islamic clergy successfully objected under the grounds of theodicy. Not until 1754 was the artillery school reopened on a semi-secret basis. Earlier, the guilds of writers had denounced the printing press as "the Devil's Invention", and were responsible for a 53-year lag between its invention by Johannes Gutenberg in Europe in c. 1440 and its introduction to the Ottoman society with the first Gutenberg press in Istanbul that was established by the Sephardic Jews of Spain in 1493 (who had migrated to the Ottoman Empire a year earlier, escaping from the Spanish Inquisition of 1492.) However, the printing press was used only by the non-Muslims in the Ottoman Empire until the 18th century. In 1726, Ibrahim Muteferrika convinced the Grand Vizier Nevşehirli Damat İbrahim Pasha, the Grand Mufti, and the clergy on the efficiency of the printing press, and later submitted a request to Sultan Ahmed III, who granted Muteferrika the permission to publish non-religious books (despite opposition from some calligraphers and religious leaders.) Muteferrika's press published its first book in 1729, and, by 1743, issued 17 works in 23 volumes (each having between 500 and 1,000 copies.)