The comparison between the United States in 1790 and Australia in 1891, with which Mr. _A. F. Weber_ opens his essay on _The Growth of Cities in the Nineteenth Century_[10] well illustrates how the tendency of population toward agglomeration in cities is one of the most striking social phenomena of the present age. Both countries were in nearly a corresponding state of development at the time of bringing them into the comparison. The population of the United States in 1790 was 3,929,214; that of Australia in 1891 was 3,809,895; while 3.14 per cent of the people of the United States were then living in cities of ten thousand or more inhabitants, 33.20 per cent of the Australians are now living in such cities. Similar conditions or the tendency toward them are evident in nearly every country of the world. What are the forces that have produced the shifting of population thus indicated; what the economic, moral, political, and social consequences of it; and what is to be the attitude of the publicist, the statesman, and the teacher toward the movement, are questions which Mr. Weber undertakes to discuss. The subject is a very complicated and intricate one, with no end of puzzles in it for the careless student, and requiring to be viewed in innumerable shifting lights, showing the case in changing aspects; for in the discussion lessons are drawn by the author from every country in the family of nations. Natural causes--variations in climate, soil, earth formation, political institutions, etc.--partly explain the distribution of population, but only partly. It sometimes contradicts what would be deduced from them. Increase and improvement in facilities for communication help the expansion of commercial and industrial centers, but also contribute to the scattering of population over wider areas. The most potent factors in attracting people to the cities were, in former times, the commercial facilities they afforded, with opportunities to obtain employment in trade, and are now the opportunities for employment in trade and in manufacturing industries. The cities, however, do not grow merely by accretions from the outside, but they also enjoy a new element of natural growth within themselves in the greater certainty of living and longer duration of life brought about by improved management and ease of living in them, especially by improved sanitation, and it is only in the nineteenth century that any considerable number of cities have had a regular surplus of births over deaths. Migration cityward is not an economic phenomenon peculiar to the nineteenth century, but is shown by the study of the social statistics and the bills of mortality of the past to have been always a factor important enough to be a subject of special remark. It is, however, a very lively one now, and "in the immediate future we may expect to see a continuation of the centralizing movement; while many manufacturers are locating