But how was such an undertaking to be begun? Where were the materials; and even granting that they were to be procured, how was such a mass of general reading as must be consulted, to be utilised? Mr Bancroft's first step was to solve this difficulty. He decided to establish at his own cost, in San Francisco, a library of reference, which should contain all the books to be had for money which could throw any light on the subject. With this end in view, he appointed agents in all the principal cities of the world, whose business was to frequent sales, examine book catalogues, and effect the purchase of any volumes which seemed likely to contain useful information. Of course by such a system many books were transmitted to headquarters which ultimately proved to be of little or no value; but this was inevitable in the course of purchases of such magnitude. And notwithstanding all drawbacks of the kind, the collection has gradually increased, until it is said now to consist of between eighteen and twenty thousand volumes, including pamphlets; whether this number also includes manuscripts, we are unable to say. The acquisition of these works has been occasionally furthered by adventitious circumstances. The Mexican war, for instance, was the means of throwing in Mr Bancroft's way some highly valuable documents, which, under favourable circumstances, would have remained the property of their lawful owners; these, contained in four volumes, are a set of parchment records of the Church in Mexico between the years 1530 and 1583, and apart from their historical value, have an interest to the bibliopolist as containing autographs of many celebrated men, amongst others of Philip II., Torquemada, Las Casas, and Zumarraga, first Archbishop of Mexico. This last-named worthy is notorious for his act of insensate bigotry in destroying the Aztec records, and thereby depriving the world of the history of that race; he burned the hieroglyphic paintings of Anahuac in the public square of Tlatelolco, much as Ximenes did with eighty thousand Moorish manuscripts in Granada. These priceless records were stolen from the government archives! When the unfortunate Emperor Maximilian's library was sold, many valuable works were also obtained from that collection, which had been gathered together during a lifetime by a well-known amateur, Count Andrade. The weakest part of the arrangement of Mr Bancroft's undertaking is the manner in which the books are housed, but this is probably an unavoidable evil; they occupy the fifth story of the owner's house in Market Street, San Francisco, where they are exposed to all the risk of fire, to say nothing of the inconvenience of such a plan. The apartment in which they are kept occupies the whole length of the building, and the books are arranged upon shelves reaching from the floor to the ceiling, and running from one end of the room to the other. Let us now see how it is proposed to utilise this mass of literature for reference.