It is curious to reflect that the library, in our customary sense, is quite a modern institution. Three hundred years ago there were no public libraries in Europe. The Ambrosian, at Milan, dates from 1608; the Bodleian, at Oxford, from 1612. To these Angelo Rocca added his in Rome, in 1620. But private collections of books always existed, and these were the haunts of learning, the little glimmerin...