Scientific American Supplement, No. 312, December 24, 1881 eBook

This eBook from the Gutenberg Project consists of approximately 107 pages of information about Scientific American Supplement, No. 312, December 24, 1881.

As regards the question of safety, it is a fact that, notwithstanding the increased speed, railway accidents are fewer than they were at the slow speed.  It is also a fact, that if the whole population of London were to take a railway journey, there would be but one death arising out of it.  Four millions of journeys for one death of a passenger from causes beyond his own control is, I believe, a state of security which rarely prevails elsewhere.  As an instance, the street accidents in London alone cause between 200 and 300 deaths per annum.  This safety in railway traveling is no doubt largely due to the block system, rendered possible by the electric telegraph; and also to the efficient interlocking of points and signals, which render it impossible now for a signal man to give an unsafe signal.  He may give a wrong one, in the sense of inviting the wrong train to come in; but, although wrong in this sense, it would still be safe for that train to do so.  If he can give a signal, that signal never invites to danger; before he can give it, every one of the signals, which ought to be “at danger,” must be “at danger,” and every “point” must have been previously set, so as to make the road right; then, again, we have the facing point-lock, which is a great source of safety.

BRAKES.

Further, we have continuous brakes of various kinds, competent in practice to absorb three miles of speed in every second of time; that is to say, if a train were going 60 miles an hour, it can be pulled up in 20 seconds; or, if at the rate of 30 miles, in 10 seconds.  With a train running at 50 miles an hour, it can be pulled up in from 15 to 20 seconds, and in a distance of from 180 to 240 yards.  Moreover, in the event of the train separating into two or more sections, the brakes are automatically applied to each section, thereby bringing them to rest in a short time.  Another cause of safety is undoubtedly the use of weldless tires.  I was fortunate enough to attend the British Association meeting many years ago at Birmingham, and I then read a paper upon weldless tires, in which I ventured to prophesy that, in ten years’ time, there would not be a welded tire made; that is one of the few prophecies that, being made before the event, have been fulfilled.  I may perhaps be permitted to mention, that at the same time I laid before the section plans and suggestions for the making of the cylindrical parts of boilers equally without seam, or even welding.  This is rarely done at the present time, but I am sure that, in twenty years’ time, such a thing as a longitudinal seam of rivets in a boiler will be unknown.  There is no reason why the successive rings of boiler shells should not be made weldless, as tires are now made weldless.

MOTORS.

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Scientific American Supplement, No. 312, December 24, 1881 from Project Gutenberg. Public domain.
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