Notes on Railroad Accidents. Adams Charles Francis
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Telescoping, however, was an incident of crushing, and a peculiarly American incident, which is not without a certain historical interest; for the particular feature in car construction which led directly to it and all its attendant train of grisly horrors furnishes a singular and instructive illustration of the gross violations of mechanical principles into which practical, as opposed to educated, mechanics are apt constantly to fall, – and in which, when once they have fallen, they steadily persist. The original idea of the railroad train was a succession of stage coaches chained together and hauled by a locomotive. The famous pioneer train of August 9, 1831, over the Mohawk Valley road was literally made up in this way, the bodies of stage coaches having been placed on trucks, which "were coupled together with chains or chain-links, leaving from two to three feet slack, and when the locomotive started it took up the slack by jerks, with sufficient force to jerk the passengers, who sat on seats across the tops of the coaches, out from under their hats, and in stopping they came together with such force as to send them flying from their seats." On this trip, it will be remembered, the train presently came to a stop, when the passengers upon it, with true American adaptability, set their wits at once to the work of devising some means of remedying the unpleasant jerks.4 "A plan was soon hit upon and put in execution. The three links in the couplings of the cars were stretched to their utmost tension, a rail, from a fence in the neighborhood, was placed between each pair of cars and made fast by means of the packing yarn from the cylinders." Here was the incipient idea of couplers and buffers improvised by practical men, and for a third of a century it remained almost unimproved upon, except by the introduction of a spring upon which coupler and buffer played. The only other considerable change made in the earlier days of car construction was by no means an improvement, inasmuch as it introduced the new and wholly unnecessary danger of telescoping.
The original passenger cars, however frail and light they may have been, were at least, when shackled together in a train, continuous in their bearings on each other, – that is, their sills and floor timbers were all on a level and in line, so that, if the cars were suddenly pressed together, they met in such a way as to resist the pressure to the extent of their resisting power, and the floor of one did not quietly slide under or over that of another. The bodies of these cars were about thirty-two inches from the rails. This was presently found to be too low. In raising the bodies of the cars, however, the mechanics of those days encountered a practical difficulty. The couplings of the cars built on the new model were higher than those of the old. They at once met, and, as they thought, no less ingeniously then successfully overcame this difficulty, by placing the couplings and draw-heads of their new cars below the line of the sills. This necessitated putting the platform which sustained the coupling also beneath the sills, and in doing that they disregarded, without the most remote consciousness of the fact, a fundamental law of mechanics. With a possible pressure, both sudden and heavy to be resisted, the line of resistance was no longer the line of greatest strength. During thirty years this stupid blunder remained uncorrected. It was as if the builders during that period had from force of habit insisted upon always using as supports pillars which were curved or bent instead of upright. At the close of those thirty years also the railroad mechanics had become so thoroughly educated into their false methods that it took yet other years and a series of frightful disasters, the significance of which they seemed utterly unable to take in, before they could be induced to abandon those methods.
The two great dangers of telescoping and oscillation were directly due to this system of car construction and of train coupling, – and telescoping and oscillation were probably the cause of one-half at least of the loss of life and the injuries to persons incident to the first thirty years of American railroad experience. The badly built and loosely connected coaches of every train going at any considerable rate of speed used then to swing and roll about and hammer against each other after a fashion which made the infrequent occurrence of serious disaster the only fair subject for surprise. In case of a sudden stoppage or partial derailment, the train stopped or went on, not as a whole, but as a succession of parts, while the low platforms and slack couplings fearfully increased the danger; – for, if the train held together, the cars in stopping were likely to break off the platforms, making of what remained of them a sort of inclined plane over which the car-bodies rode into each other at different levels; or, if the couplings, as was more probable, held and the train did not part, the swaying and swinging of the loosely connected cars was almost sure to throw them from the track and break them in pieces. The invention through which this difficulty was at last overcome, simple and obvious as it was, is fairly entitled, so far as America at least is concerned, to be classed among the four or five really noticeable advances which have of late years been made in railroad appliances. It contributed unmistakably and essentially to the safety of every traveller. Known as the Miller platform and buffer, from the name of the inventor, it was, like all good work of the sort, a simple and intelligent recurrence to correct mechanical principles. Miller went to work to construct cars in such a way as to cause them to come in contact with each other in the line of their greatest resisting power, while in coupling them together in trains he introduced both tension and compression; – that is he, in plain language, brought the ends of the heavy longitudinal floor timbers of the separate cars exactly on a line and directly bearing on each other, and then forced them against each other until the heavy spring buffers which played on those floor timbers were compressed, when the couplers sprung together and the train then stood practically one solid body from end to end. It could no more swing or crush than a single car could swing or crush. It then only remained to increase the weight and to perfect the construction of the vehicles to insure all the safety in this respect of which travel by rail admitted.
Simple as these improvements were, and apparently obvious as the mechanical principles on which they were based now seem, the opposition for years offered to them by practical master-mechanics and railroad men would have been ludicrous had it not been exasperating. There was hardly a railroad in the country whose officers did not insist that their method of construction was exceptional, it was true, but far better than Miller's. It was maintained that the slack couplings were necessary in order to enable the locomotives to start the trains, – that a train made up without the slack, on Miller's plan, could not be set in motion, and that if it was set in motion it must twist apart at every sharp curve etc. The ingenuity displayed in thus inventing theoretical objections to the appliance far exceeded that required for inventing it, and indeed no one who has not had official experience of it can at all realize the objecting capacity of the typical practical mechanic whose conceit as a rule is measured by his ignorance, while his stupidity is unequalled save by his obstinacy. Even when Miller's invention for one reason or another was not adopted, the principles upon which that invention was founded, – the principles of tension, cohesion and direct resistance, – at last forced their way into general acceptance. The long-urged objection that the thing was practically impossible was slowly abandoned in face of the awkward but undeniable fact that it was done every day, and many times a day. Consequently, as the result of much patient arguing, duly emphasized by the regular recurrence of disaster, it is not too much to assert that for weight, resisting power, perfection of construction and equipment and the protection they afford to travellers, the standard American passenger coach is now far in advance of any other. As to comfort, convenience, taste in ornamentation, etc., these are so much matters of habit and education that it is unnecessary to discuss them. They do not affect the question of safety.
A very striking illustration of the vast increase of safety secured through this improved car construction was furnished in an accident, which happened in Massachusetts upon
3
Ante pp. 18-19.
4
Railroads: their Origin and Problems, p. 49.