additions continually accruing from the titles of new books received after the printing of the volume,[96:1] which is further supplied with guards to allow of interleaving. It has been computed that each volume would contain 9000 titles, after which it must be divided, and that the Reading Room will accommodate 2000 volumes, providing room for eighteen millions of titles, or, at the present rate of cataloguing, for the accumulation of three centuries to come. In 1880, just before the introduction of printing, there was not room to place another volume. A column of the type used in printing the catalogue weighs ten pounds, so that supposing the work, when through the press, to consist of 600 volumes averaging 250 columns each, a million and a half pounds' weight of type will have been employed. From the preparation of the catalogue for strictly Museum purposes, we pass to the arrangements for its issue to the public. Here we are confronted by two very remarkable facts—one as gratifying as the other is the reverse. For the _original subscribers_ the Museum Catalogue is one of the cheapest books in the world. At its commencement it was not expected that more than fifteen parts could be issued annually, and the annual subscription was fixed at three pounds. In fact, however, the rate of publication has for some years past averaged thirty parts, while the terms of subscription remain unaltered. The subscription is, therefore, virtually reduced by one-half, and the cost of each part, with its 250 columns and 5000 titles, is just two shillings. It may be doubted whether equal liberality has ever been shown by any public institution. The case, however, of the subscribers of the future is far otherwise, or rather say would be, if such subscribers could exist. Nobody will take an imperfect catalogue, and the sum required for the parts already printed is an almost insuperable obstacle in the way of new subscribers, and an effectual bar to the further dissemination of the catalogue, except by donation. It would be well worth while to offer the parts already printed as a bonus, at a nominal or greatly reduced price. Unfortunately, however, the number of copies printed during the first year was comparatively limited, and the impression, as regards these, would be exhausted almost immediately. The difficulty would disappear if the Museum possessed that indispensable auxiliary to its progress, a photographic department, in which the photographer's salary and the cost of chemicals should be paid by the State; thus allowing photographic work to be done gratuitously for the institution, and at a merely nominal rate for the public. In this case the deficient volumes would be supplied without any expense whatever, and the offer of the perfected sets to the public at a nominal cost would probably ensure sufficient subscribers for the remainder of the work. Until this great step towards the popular dissemination of the Museum's treasures in all