It was in this temple that the successive additions to the Alexandrian library were deposited, when the apartments of the Museum became full.  In the end there were four hundred thousand rolls or volumes in the Museum, and three hundred thousand in the Serapion.  The former was called the parent library, and the latter, being, as it were, the offspring of the first, was called the daughter.

Ptolemy Philadelphus, who interested himself very greatly in collecting this library, wished to make it a complete collection of all the books in the world.  He employed scholars to read and study, and travelers to make extensive tours, for the purpose of learning what books existed among all the surrounding nations; and, when he learned of their existence, he spared no pains or expense in attempting to procure either the originals themselves, or the most perfect and authentic copies of them.  He sent to Athens and obtained the works of the most celebrated Greek historians, and then causing, as in other cases, most beautiful transcripts to be made, he sent the transcripts back to Athens, and a very large sum of money with them as an equivalent for the difference of value between originals and copies in such an exchange.

In the course of the inquiries which Ptolemy made into the literature of the surrounding nations, in his search for accessions to his library, he heard that the Jews had certain sacred writings in their temple at Jerusalem, comprising a minute and extremely interesting history of their nation from the earliest periods and also many other books of sacred prophecy and poetry.  These books, which were, in fact, the Hebrew Scriptures of the Old Testament, were then wholly unknown to all nations except the Jews, and among the Jews were known only to priests and scholars.  They were kept sacred at Jerusalem.  The Jews would have considered them as profaned in being exhibited to the view of pagan nations.  In fact, the learned men of other countries would not have been able to read them; for the Jews secluded themselves so closely from the rest of mankind, that their language was, in that age, scarcely ever heard beyond the confines of Judea and Galilee.

Ptolemy very naturally thought that a copy of these sacred books would be a great acquisition to his library.  They constituted, in fact, the whole literature of a nation which was, in some respects, the most extraordinary that ever existed on the globe.  Ptolemy conceived the idea, also, of not only adding to his library a copy of these writings in the original Hebrew, but of causing a translation of them to be made into Greek, so that they might easily be read by the Greek and Roman scholars who were drawn in great numbers to his capital by the libraries and the learned institutions which he had established there.  The first thing to be effected, however, in accomplishing either of these plans, was to obtain the consent of the Jewish authorities.  They would probably object to giving up any copy of their sacred writings at all.