"During your time, accidents were not uncommon--in fact, I might say quite common, judging from the old chronicles; but we have never had an accident yet upon any of our lines. There have been, of course, breaks and delays; but as each train is in communication with each other, and with each end, and with the chief of the exhausting department, everything is known at all times regarding the position of trains and their condition." Striking a match, he continued: "No train could run into the one ahead of it, for the reason that there will always be a cushion of air between them; and further, were any ordinary number of runners to break at one time, the train would not be affected by the loss." "How wonderful, yet how simple!" exclaimed Cobb, lost in admiration. "But I am at a loss to understand why the people of my time did not discover and put into operation the same project." "Perhaps someone did discover the principle, but had not the means to test his theory," Rawolle returned. "How long has this system been in operation?" "About thirty years," he replied, after a moment's thought. "Tell me one other thing," said Cobb; "has the pneumatic railroad superseded all other kinds?" "Oh, no; by no means. There are railroads all over the United States, and very much the same style of your day, excepting the great improvements which have been made, and also the one other most important fact, that all engines are run by electricity. The pneumatic lines are through lines only, and are for rapid transit between very distant points, and only for passengers, mail, and express. All freight is sent by the other roads." "Then, the towns, excepting the great centers, are connected by electric railroads for inter-transportation?" "Yes; the pneumatic is only an auxiliary to the rest of the roads--a means only of overcoming great distances quickly." "And what is considered good speed for the electric roads?" "Seventy-five miles per hour for passenger trains, and fifty for freights." "Then, they must be very differently constructed from those of old," exclaimed Cobb. "They have very different roadbeds, and, of course, different engines. But enough for the present," looking at his watch. "It is 18 dial, and we had better get into the sleeper and prepare for supper, for we are almost at Salt Lake." CHAPTER X After supper, and when settled back once again in the cushions of their sleeper, Cobb immediately resumed the conversation about the pneumatic roads. "They must be very rich and powerful corporations, these which own such lines as this?" "No," returned Rawolle; "for they are not owned by individuals, but by the government. All railroads in the United States are in the hands of the government, and are operated with a view to just covering expenses." "Are the rates of passage high?" "We do not consider them so. There is one fixed rate throughout the country of one cent per mile."