of arrangement and classification now in vogue meet the requirements of classification, provision of space, and saving of space, and to this end we will proceed to describe in detail a typical specimen of each.
(1) The fixed-location system at the British Museum. The various presses are denoted by a series of Arabic figures, ranging from one to 14,000, and the whole space is divided up among the departments of human knowledge, according to a rough scheme of classification hereinafter set forth. The numeration of the presses is not successive, the originators of the plan being conscious that it was impossible to foresee the relative rates of increase in the literature of the various subjects. It was no doubt regarded as possible that the omitted numbers would in course of time be assigned to new presses erected in new buildings, or otherwise separated from their place in the original scheme. The shelves are denoted by the successive letters of the alphabet, sometimes used singly, sometimes repeated or used in conjunction. The origin of this lettering is that the presses in what is now the Hebrew Library, and in other parts, the contents of which were shifted to the iron structure round the Reading-room after the latter was built, were only one storey in height, and when it was decided to space them out over two storeys intermediate letters had to be invented wherewith to distinguish the intervening unoccupied shelves. In order that the press-mark of a book may show on which storey it is to be found, and
