Besides the imperial library, the churches and religious houses of Constantinople were enriched with collections of manuscripts more or less extensive. And not only in the favored City but in the regions adjacent--in the islands of the Ægean, on Cyprus, and in many other quarters--manuscripts were collected, transcribed, and preserved. (Isaac Taylor.) Constantinople, while it continued to be the center of learning and literature, was by no means the exclusive center; for the enterprise of collecting and treasuring books was widely disseminated. "No spot," says Isaac Taylor, "was more famed for the production of books than Mount Athos--the lofty promontory which stretches from the Macedonian coast far into the Ægean Sea." And the churches, too, in wide areas, became depositories of books, especially of the Bible or parts thereof, liturgical volumes, and works of devotion. There were also church libraries at Jerusalem, at Rome, and in many other localities. One at Cæsarea is said to have contained, as augmented by Eusebius, the historian, about thirty thousand volumes. Gradually into all these regions--into Crete, Italy, western Europe; and even into the British Isles; into Palestine, Arabia, and northern Africa--numerous monasteries with their collections of books were established and maintained. These religious houses were everywhere peopled by recluses, among whose principal duties was the care for and the transcription of books. For long periods of time, however, and universally throughout Europe during the Middle Ages, there was, as has already been noted, a great decline in learning and but little interest in books--the exception to this condition being almost wholly limited to the occupants of the religious institutions. It is the record of history that, as civilization lost its energy in wide areas--especially throughout Gaul--intellectual darkness spread over all the country, so much so that there was hardly a layman and only a few among the clergy who could even read. Mighty leaders of state shared in this intellectual desuetude. Even Charlemagne, that great ruler who welded divergent peoples into one body to resist Saracen and savage, and who did much to institute and promote educational movements, lived and died with modicum attainments of technical learning. It is recorded of him in witness of his meager achievements in this direction that "He could read and understand Latin--but how well, perhaps, we had better not too closely inquire; he tried late in life to learn to write, but his progress in that direction did not greatly impress his biographer." Macaulay asserts it of the twelfth century that "There was then, through the greater part of Europe, very little knowledge, and that little was confined to the clergy. Not one man in five hundred could have spelled his way through a psalm. Books were few and costly. The art of printing was unknown."