It was not abandoned. Some inventive genius over in Los Angeles devised a motor-truck with a different sort of wheel than had ever been seen before. Inside there were the flanged wheels for the contact upon the steel rail, and, just outside of these, heavy rubber-tired wheels for use upon the highway. The problem of that little road, both for freight and passenger traffic was solved. No longer must it await the passengers and goods who found their way to its station at thriving and growing El Centro. Its combination trucks took the city streets very easily; they could go to any hotel or merchant's door, receive passengers or freight, and then, making their way to the railroad terminal, by a simple mechanical device mount the rail and go hurrying off to Holtville, with the tractive advantage of the steel rails over even the well-paved dirt road that already I have shown you. Moreover it became no longer necessary for the road to go to the expense of train-despatching. If two of its "trains" met midway on the line, by the use of this same ingenious mechanical device, one of them could remain on the rails and the other go to the earth surface alongside of it. This then became the ordinary operation of the line, that trains going east upon the track had the right to the rails, while those going west would take to the dirt. What could be simpler? The flexibility of the gasolene-motor unit is indeed astounding. It is not inconceivable that a device such as I have indicated should be so extended as to permit a motor-truck or passenger-car unit to go far beyond the limits of the rail terminals. In other words, why should Holtville be the terminal of the Holtville interurban? If there is a load of freight eight miles to the east of it, why not send the "train" on the highway for that eight miles to let it pick up the freight. The correlation of the highway with the steam railroad is a topic of almost unending fascinations. By it the branch lines of our big roads and the main stems of our small ones may be continued almost indefinitely. There undoubtedly are many cases where it would be both more practical and more profitable for the railroad to abandon the branch line entirely and use in its stead the nearest parallel highway. Into this possibility there enters, of course, the question of the congestion of that parallel highway. One of the arguments that I have just used for the placing of the motor-truck upon the railroad track is to give a much needed relief to the highroad. Yet here, as in so many other places, one cuts the cloth to meet the situation. In one instance it might be most advisable to use the highroad as a supplement to the railroad track; in another it would be a great mistake.