Rome having conquered Athens, we hear no more of the Athenian libraries, but the seat of ancient learning was transferred to Alexandria, where were gathered under the liberal sway of the Ptolemies, more books than had ever been assembled together in any part of the world. Marc Antony presented to Cleopatra the library of the Kings of Pergamus, said to have contained 200,000 rolls. There is no space to sketch the ancient libraries, so scantily commemorated, of Greece. Through Aristotle's enthusiasm for learning, as it is believed, the Ptolemies were fired with the zeal of book-collecting, and their capital of Alexandria became the seat of extensive libraries, stored in the Brucheion and the Serapeum. Here, according to general belief, occurred the burning of the famous Alexandrian library of 700,000 volumes, by the Saracens under Omar, A. D. 640. If any one would have an object lesson in the uncertainties of history and of human testimony, let him read the various conflicting accounts of the writers who have treated upon this subject. The number of volumes varies from 700,000, as stated by Aulus Gellius, to 100,000 by Eusebius. The fact that in ancient times each book or division of an author's work written on a roll of papyrus was reckoned as a volume, may account for the exaggeration, since the nine books of Herodotus would thus make nine volumes, and the twenty-four of Homer's Iliad, twenty-four volumes, instead of one. So, by an arbitrary application of averages, the size of the Alexandrian Library might be brought within reasonable dimensions, though there is nothing more misleading than the doctrine of averages, unless indeed it be a false analogy. But that any library eight hundred years before the invention of printing contained 700,000 volumes in the modern sense of the word, when the largest collection in the world, three centuries after books began to be multiplied by types, held less than 100,000 volumes, is one of the wildest fictions which writers have imposed upon the credulity of ages. I cannot even touch upon the libraries of the Romans, though we have very attractive accounts, among others, of the literary riches of Lucullus, of Atticus, and of Cicero. The first library in Rome was founded 167 B. C. and in the Augustan age they multiplied, until there were twenty-nine public libraries in Hadrian's time, 120 A. D. The emperor Julian, in the fourth century, was a founder of libraries, and is said to have placed over the doors this inscription: "_Alii quidem equos amant, alii oves, alii feros; mihi vero a puerulo mirandum acquirendi et possidendi libros insedit desiderium._"