From this standpoint we get a fair view of the tremendous strides of library growth in the United States during the nineteenth century. The sixty-four libraries of 1800 have grown to well nigh four thousand, not counting those of less than 1000 volumes; and the less than 500,000 volumes of 1800 have increased to well nigh 30,000,000, omitting those in libraries of less than a thousand volumes. Over six hundred libraries in the United States take rank as 20,000-volume libraries and over, at the end of the century; and in the six statistical years between 1888 and 1893, which mark the greatest ratio of increase in volumes, there was a growth equal to 66 per cent over all that had preceded. Nor has the century been more triumphant and wonderful in the accumulation of volumes and the number of book repositories than in the variety of systems and multiplicity of agencies by means of which library information is arranged and disseminated. Conspicuous among these has been the inauguration and growth of the free library system, by means of which public funds are provided for the support of libraries whose use is free to all. Hardly less conspicuous, and perhaps even more far reaching, has been the adoption by many States of the school-district library system, which draws upon a certain proportion of the school fund for the collection and maintenance of the district library. Again, most of the States have established libraries of their own for public use, and as centres to which may be gathered and whence may be disseminated the knowledge that appertains to the respective State localities. Special library systems have grown into great favor, covering and encouraging collections of historic works, of scientific literature, of information relating to law, medicine, theology, etc. In fact, there is hardly a line of investigation and mental activity that has not come to be represented in its library collections. [Illustration: THE CARNEGIE FREE LIBRARY, PITTSBURGH, PA.]