others, all in letter A after the article Aristotle to the end. They have cost, in round figures, £2450, or about £110 each. Arrangements lately completed will diminish this cost by nearly a sixth, and the sum economised will be available for additional printing. It ought to be stated that all the extra work entailed by printing has been performed by the ordinary Museum staff, with no addition to its resources, except an arrangement by which two gentlemen work two or three hours' overtime. It is of course apparent that if a large portion of the catalogue is to be put within reach of the present generation the scale of operations must be greatly enlarged. We may one day see the whole of the printing of the Museum a special department, like the Clarendon or Cambridge University press, with a head and a staff of its own, and carrying on operations by the side of which those I have been describing will appear diminutive. At present the Museum force and the Museum grant are nicely adapted to each other. With a stronger staff we could easily spend much more money, with a weaker staff we could not spend what we do. Every effort is of course made to expend the full amount within the year, not only that it may not return unused into the Exchequer, but, from consideration to the just claims of our printers, who have engaged a number of extra hands whom they cannot afford to keep idle. Hence, as I have stated, we are content with a single revise, and deliberately prefer systematic energy to minute accuracy. Misprints and other oversights will, no doubt, be detected, which a more deliberate procedure would have obviated. I do not desire to have the air of apologising for a catalogue which, even if tried by a severe standard, will, I am persuaded, be pronounced a creditable work; but I wish it to be understood that these blemishes, as well as some defects of arrangement manifested in long sets of cross-references, are not unknown or overlooked. They will diminish as the work proceeds; confident, meanwhile, of a generous construction, we are deliberately of opinion that it is infinitely better to run the risk of letting them pass than to open a door to the capital enemy of all good administration—arrear. Other shortcomings are necessitated by the fact that the Museum Library is not an inert mass, but a living organism. You have not to deal with a closed collection of books like the King's Library, whose authors are dead, and to which no addition can ever be made. The very titles before you have been prepared during the last forty years by twice forty persons of various idiosyncrasies, whose work, with every care, it is often no easy matter to harmonise. While the product of their heterogeneous authorship is at press, the Accession Catalogue is in progress under independent management; thousands of titles are annually written and entered which will one day have to be amalgamated with the general series, and discrepancies must sometimes occur. Moreover, the