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 issue. On the other hand, each new edition of Haydn's "Dictionary of Dates" incorporates all the old matter with the new. Directories, if local, should be preserved en masse if space admits, with a view to the future historian of the town, whose advent may be safely looked for in the smallest library. With a similar object, all editions of works by local writers should be preserved. It is a delicate matter to slight a donor, but the blow will fall lightly if he is long since defunct, and this consideration will often lead to a wholesale clearance of the stuff which well-meaning people from time to time have shot into local libraries.

The exchange of duplicates is a practice which has not yet reached the development it merits. In several countries on the Continent there are elaborate regulations dealing with the disposal of duplicates, but it would be of great service to scholars if means could be devised for an extension of the principle to international exchange. The British Museum from time to time distributes its duplicates to other libraries, but it is to be feared that the more valuable of them remain quite unused in their new homes. If these could have been exchanged for some of the vast accumulations of duplicates in the Bibliotheque Nationale, the gain to both institutions might have been considerable. The methods of disposing of duplicates accumulated in the national libraries of Italy, as set forth in a recent decree of the Minister of Education