KAILWAY ACCIDENTS. 



with an independent brake and brakesman. This would 

 certainly cause a considerable increase in the working expenses 

 of the faster class of trains, but the public safety is a matter 

 of too great importance to be postponed to considerations of 

 this kind. 



30. In attempting to avoid one source of danger another is 

 often produced. When an obstacle is seen on the rails before a 

 train moving with great speed, all means must of course be used 

 to bring the train suddenly to rest. But if this be not done 

 with great caution and skill, danger may be produced even more 

 serious than that from which it is attempted to escape. The 

 means of stopping a train are, the brake on the tender, the 

 brakes on the vehicles composing it, and, in fine, reversing the 

 action of the engine. This process consists in so changing the 

 motion of the slides, that the steam shall obstruct instead of 

 accelerating the pistons. In this way the whole force of the 

 steam is suddenly made to resist the progressive motion of the 

 train. 



31. This is a dangerous process. The progress of the engine 

 is arrested by an agent which does not act on the vehicles which 

 follow it. The latter are consequently urged against the engine 

 and against each other with all the force of which the engine is 

 deprived by the back action of the steam. The effect is nearly 

 the same as if an engine acting behind the train suddenly pushed 

 the train against the engine in front. The effect of this is an 

 obvious tendency to drive the intermediate carriages off the 

 rails by doubling up the train. 



Before reversing the engine, or even applying the brake to the 

 tender, it is therefore always advisable to warn the brakesmen 

 to apply the brakes to the vehicles composing the train. This 

 being done, and the brake being then applied to the tender, 

 there is less danger in reversing the steam on the engine. 



But it unfortunately happens that in the emergencies in which 

 these extreme measures are demanded, there is rarely time to 

 observe these precautions. The prudence of providing a signal 

 on the tender which shall be within view of the brakesmen, and 

 seats for the latter from which they can always see such signal, 

 is so obvious that it need not here be enlarged on. 



32. We must not dismiss this subject without noticing the 

 ingenious application of detonating substances, now called fog 

 signals. 



These are detonating balls, which on being crushed explode 



with the report of a pistol. When a train is stopped on the 



line by an accident, or in general when an obstacle is found upon 



the railway from any unexpected cause, and which cannot be 



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