The number of what may be called books published by the fathers of the church in the first centuries of the Christian era was great. Origen wrote 6,000; many of these were more properly tracts; but his polyglot version of the Bible (most of which has perished), and his great work against Celsus, were laborious works indeed. Of the writings of the fathers generally (apart from the Evangelists) but few have descended to us. The Koran (partly compiled from the Bible) was composed by the imposter Mahomet, in the seventh century. At that epoch there were few books even in Europe, the most enlightened portion of our world, and this literary darkness prevailed three hundred years longer. A curious episode in the history of early bookmaking occurred in the sixth century, Cornelius Agrippa has related, in his Vanity of Science, that a contrivance had been invented, by which the several parts of speech in any language could be combined by a system of circles worked in an ingenious manner. The component parts--nouns, verbs, etc.--come together so as to form complete sentences--a very convenient contrivance for writers who are deficient in what we consider essentials--intellect, learning, and invention. Sir Walter Scott, in his Life of Swift, says that the dean was indebted for his entertaining and witty satire on pretending philosophers, as displayed in his Flying Island of Laputa, to the above historical fact. The machine of the Professor of Lagado, in Gulliver's Travels, for imparting knowledge and composing books on all subjects without assistance from genius or knowledge, was designed to ridicule the art invented by Raymond Tully, the individual referred to by Cornelius Agrippa. Various improvements on this mechanical mode of composition were tried, but of course with utter failure. During long periods of barbarism, entire libraries of rolls and books were destroyed by ruthless and ignorant soldiery, as in Caesar's time, when the library of 700,000 volumes which had been amassed by Ptolemy was burnt by Caesar's troops. The great library collected at Constantinople by Constantine and his successors was burnt in the eighth century. {108}