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THE ROVVELL-POTTER TRAIN STOP-ONE OF THE TWO APPROVED BV THE
The illustrations respectively show the signals set Jot safety, the track trip mechanism, and the signal set for danger.
MECHANICAL 'BRAINS SAVE LIVES
TOO many railroad wrecks! How shall they be made less frequent? During the last fiscal year, in this country, no fewer than nine hundred and thirty-two people were killed, and fourteen thousand, three hundred and seven persons maimed or otherwise seriously hurt, by smashups on the rail. It was a frightful carnage. A considerable battle, indeed, might have been fought without greater loss. But there is good reason for supposing that the number of slain and wounded in the present year will be at least as great, and so on for every subsequent twelvemonth.
That is to say. unless something is done to alter radically the conditions which give rise to mishaps of the kind.
It is a very serious problem, and the government is trying hard to find at least a partial solution for it. Congress, not long ago, handed the matter over to the Interstate Commerce Commission, with authority to appoint a board to investigate the whole subject.
This board, in a report newly prepared, declares that the fundamental cause of the trouble is to be found in the American tendency to hurry. People in this country are so anxious to do things quickly that, to a great extent, they ignore caution. Here is the principal reason why railroad wrecks, which are rare occurrences in England and on the continent of Europe, are so frightfully frequent in the United States. Nevertheless, taking conditions as they are, much sort of mistake may be avoided. They have contrived a number of expedients by which an over-run danger signal gives warning in the cab of the locomotive, automatically. These, which are called "cab signals" are already in use to a considerable extent abroad. Other devices, which not only give warning, but actually stop the train, are still more effective, reducing the human
may be done to lessen the number of such accidents by the adoption of certain mechanical measures of precaution— most important of all, the automatic train-stop.
Such a stop provides for automatic train control. It is a device to prevent the over-running of stop signals by trainmen. Often it happens that the engineer of a locomotive fails to notice the fact that a signal is set for danger. It warns him to bring his train to a halt; but, failing to recognize it, he runs past, and in many instances a disaster is the consequence.
The ingenuity of inventors lias been taxed to devise a means by which this
Thk Device For Contact With The Rail. Carried Beneath The Locomotive.
factor in the railroad equation to a minimum.
Many such automatic train-stops have been to a greater or less extent perfected. In most instances they are electrical contrivances, and operate by setting the brakes of the train. Thus, for example, one of them—already tried with some
J. E. PAGE. OF KANSAS CITY. AND HIS PATENT COACH. This car has an anti-telescoping device, the steel floor at each end terminating at an angle, so that cars in collision may slide by each other.
satisfactorily have received the final approval of the board.
These two, which have been tested under actual traffic conditions, are both of the mechanical trip type. One of them, known as the Rowell-Potter trainstop, is an arrangement by which a bar lying parallel and close to one of the rails of the track is lifted a short distance above the rail whenever the visual signal is set for danger. Under such circumstances, the bar, coming into contact with
an air-brake valve, suspended from one of the trucks of the tender, opens the valve and applies the brake.
Bars at the side of the track are provided in duplicate at each signal point, one of them 180 feet in advance of the other, so that, if the first One should by any accident fail to operate, the second would bring the train to a halt. Power to operate the stop, as well as to work the semaphore signals of the system, is derived from the pressure of the wheels
Thk S. H. Harrinc.ton Mechanical
of passing trains on levers fixed close to the rails, these levers serving to wind up a coil spring.
The other automatic stop approved by the board is the invention of S. H. Harrington, and has been in experimental and successful use for over two years on the Northern Railroad of New Jersey. It works "overhead"—that is to say, the device fixed at the roadside is suspended, fifteen feet above the track, in such a way as to come into contact with a projecting arm of an air-brake valve on the top of the cab in the locomotive, the opening of which valve applies the brake. The roadside contrivance consists of a weight suspended on the end of a chain, which, hanging free, operates the engine valve by its mere inertia, when it strikes. At the same time, it has the great advantage of failing to zvork when a train is going very slowly—say. five miles an hour or less. Under such circumstances—when a precaution of the kind is not wanted— the weight simply drags over the operating rod on the locomotive, producing no effect.
It will be observed that the automatic stop does not in any way insure the correctness of signals. Its only function is to correct the error of the engineman who runs past a danger warning. This, however, is of utmost importance, inasmuch as many bad accidents are caused by the failure of locomotive engineers to observe, understand, and obey signals. Failure to observe them may be due to fog, snow, extinction of signal lights, or smoke from other trains. The engineman may fail to understand signals because of their complexity, or for the reason that his attention is distracted. Intentional failure to obey them is rare. The automatic stop, however, eliminates almost entirely the element of human fallibility. Furthermore, experience has shown that engineers are much more careful to heed danger signals when it is certain that disobedience of such signals will be detected.
The board confidently expects that the automatic stop will be developed to a point where, like the block signal, the car-coupler, and the train-brake, it will be available to railroads generally, and will greatly contribute to the safety of train operation. Already such contrivances are in actual use to some extent—for example, on the Boston Elevated, the New York City Subway, the Philadelphia Subway, and the underground lines in London, England. Mechanical trip train-stops of similar design, worked by electric motors, are also in use in the tunnels under the Hudson River between New York and Hoboken. Officers of these roads are unanimous in testifying to their satisfactory operation, and
on a number of occasions they have been the means of preventing collisions.
The board has likewise offered to make practical tests of two kinds of cab signals, to which an automatic train-stop can be attached if desired. One of these is the invention of E. F. Clement, of Philadelphia. The other is owned by the Railway Audible Signal Company, of London, and is now in use on the Great Western Railroad in England. Its essential feature is a short contact rail in the middle of the track at the signal point. This rail engages with a device beneath the engine, showing a danger signal in the cab and blowing the whistle of the locomotive.
The board has found itself called upon to give a good deal of consideration to the question of locomotive headlights. In seven States of the Union, Arkansas, Montana, North Carolina, Oklahoma,
Elkctric Automatic Stop On Trollky Line In Washington State. When the signal is set for danger, a metal rod smashes a glass tube on top of the car. and thus sets the brakes.