Within a century very many and various forces have been at work to produce an entire change in this system of industry. The invention of the steam engine and of the machines used in the textile fabrics produced the factory system, with a high organization of industry, concentrated at certain centers. The opening of canals and the improvement of highways made possible the commerce by which the products were distributed. The cheapening of printing and the multiplication of means of advertising widened the market by concentrating the demand which was widely dispersed in place, until now the market is the civilized world. The applications of steam power to roads and ships only extended further the same development, and the telegraph has only cheapened and accelerated the means of communicating information to the same end. What have been the effects on industry? 1. The whole industry and commerce of the world have been built up into a great system in which organization has become essential and in which it has been carried forward and is being carried forward every day to new developments. Industry has been growing more and more impersonal as far as the parties to it are concerned. Our wants are satisfied instantaneously and regularly by the coöperation of thousands of people all over the world whom we have never seen or heard of; and we earn our living daily by contributing to satisfy the wants of thousands scattered all over the world, of whom we know nothing personally. In the place of actual contact and acquaintance with the persons who are parties to the transactions, we now depend upon the regularity, under the conditions of earthly life, of human wants and human efforts. The system of industry is built upon the constancy of certain conditions of human existence, upon the certainty of the economic forces which thence arise, and upon the fact that those forces act with perfect regularity under changeless laws. If we but reflect a moment, we shall see that modern industry and commerce could not go on for a day if we were not dealing here with forces and laws which may properly be called natural because they come into action when the conditions are fulfilled, because the conditions cannot but exist if there is a society of human beings collected anywhere on earth, and because, when the forces come into action, they work themselves out, according to their laws, without possible escape from their effects. We can divert the forces from one course to another; we can change their form; we can make them expend themselves upon one person or interest instead of upon another. We do this all the time, by bad legislation, by prejudice, habit, fashion, erroneous notions of equity, happiness, the highest good, and so on; but we never destroy an economic force any more than we destroy a physical force.