The Hebrews and Greeks as well as the Romans used letters of the alphabet instead of figures for counting and calculations. The system of notation as we now have it was of gradual development. Under Theoderic the Great (454-526 A. D.), Boethius made use of certain marks or signs which were in part similar to our nine digits. This was improved upon by a pupil of Gerbeet, who used signs still more like our nine digits. But all methods of notation preceding the Arabic were unwieldly, complex, and incomplete. The system did not originate with the Arabs. As the Arabs had appropriated the Chinese discovery and use of paper, so they appropriated the Hindu system of notation. The system at first was without a _zero_: that character was added probably in the seventh century. The decimal character was used to give positional or place value to the nine digits,--the cipher having no value except in combination with the digits; it thus completed the system of notation. XVI SOURCES OF THE BOOK-MAKING INDUSTRY The making of books and the depositories of them prior to the invention of printing, and especially during the Middle Ages or from the fifth century to the fifteenth, inclusive, are matters of all but romantic interest. In the very early times and in all the principal cities of Greece and her colonies there were professional scribes who engaged in the business of copying and caring for books, the same as we now have our professional "book-keepers" (though with a different application) and our printers and librarians. This was peculiarly the condition in the later Grecian and the earlier Roman times. The accredited--though almost incredible--number of volumes in some of the ancient libraries, as at that of Alexandria--notwithstanding the slow and laborious process of their making, when every book made was a separate production--is proof positive of the extent of this industry. It was equally true of the very early times--of the times of ancient Assyria. That scribes, giving their whole attention to the production of their books, were very numerous in the period of the cuneiform writings is inferred from the immense quantity of their writings contained in the great libraries, and from the fact that in some periods almost every document is found to have been written by a different scribe. Women are known to have been employed as scribes.[62]