_The Impossibility of Long-continued Profits in the Case of Primitive Carriers._--With the growth of traffic direct competition will soon appear. A second wagon will be put on the route and then more, and the strife for freight will bring down the charges to the level of cost. For a brief season a favored drayman was able to get nearly the entire difference between the value of the goods at the point where they are made and their value at the point where they are used, _as these two values were determined by independent causes with which he had nothing to do_. Now, he and his rivals can, indeed, get the difference between the value of the goods at the one point and their value at the other; but this difference is now directly determined by the carrying charge. That charge, again, is determined by the cost of rendering the service. There was a brief interval when the value of the service and the cost of it were different amounts; but now they coincide. We shall see that the essential difference between carrying by primitive means and carrying by railroad is in the fact that in the latter case the period when value and cost are different is greatly prolonged. _The Appearance of a More Efficient Competitor._--With the growth of traffic a sailing vessel comes into use on a route connecting A with B, and the cost of thus conveying goods is less than that of conveying them over the roadway. The charge made by the sailing vessel is lower than that made by the teamsters, and the goods are thus delivered at B cheaply enough both to attract to the water route all carrying from A and to put an end to all carrying from C. The former carriers between B and C lose their business, and the makers at C lose some part of theirs, in the same way that any producer loses the traffic when he is underbid by rivals. The public is the gainer to the extent of the reduction which takes place in the cost of the goods as delivered to consumers in the market at B; nevertheless, the situation still involves a limited monopoly. The sailing vessel now has no effective rival, and can charge "what the traffic will bear," and that is very nearly the cost of conveying the goods by wagons. The advent of the vessel has benefited the public; yet it is regarded as constituting a new monopoly, and the benefit which the public gets is less than it will get when a really effective competitor of the sailing craft makes its appearance.