British Museum.—This is a great national establishment, containing a vast and constantly-increasing collection of books, maps, drawings, prints, sculptures, antiquities, and natural curiosities. It occupies a most extensive suite of buildings in Great Russell Street, Bloomsbury, commenced in 1823, and not even now finished. The sum spent on them is little less than £1,000,000. Sir Richard Smirke was the architect. The principal, or south front, 370 feet long, presents a range of 44 columns, the centre being a majestic portico, with sculptures in the pediment. Since its commencement, in 1755, the collection has been prodigiously increased by gifts, bequests, and purchases; and now it is, perhaps, the largest of the kind in the world. The library contains more than _eight hundred thousand_ volumes, and is increasing enormously in extent every year. The Reading-Room is open only to persons who proceed thither for study, or for consulting authorities. A reading order is readily procured on written application, enclosing the recommendation of two respectable householders, to “the Principal Librarian.” It is open nearly 300 days in the year, and for an average of eight hours each day. No general inspection of this room by strangers is allowed, except by a written order from the secretary, which can, however, readily be obtained on three days in the week. The porters in the hall will direct to the secretary’s office; and strangers must be careful to observe the conditions on which the order is given. The present reading-room, opened in 1857, and built at a cost of £150,000, is one of the finest apartments in the world; it is circular, 140 feet in diameter, and open to a dome-roof 106 feet high, supported without pillars. This beautiful room, and the fireproof galleries for books which surround it, were planned by Mr. Panizzi, the late chief librarian.