74 TEAR-BOOK OP FACTS. 



ELECTRO-MAGNETIC RAILWAY BREAK. 



At the late meeting of the British Association at Oxford, Dr. 

 Richardson read a paper " On an Electro-magnetic Railway Break," 

 which he illustrated with a model. He proposed the application of 

 electro-magnetism to the stoppage of railway carriages when in 

 motion, and suggested that "between the wheels on each side of 

 every railway carriage there should be placed an electro-magnet. 

 The magnet would have a slight movement up and down between 

 tw r o grooved blocks affixed to the carriage, or through a hollow 

 cylinder, if a straight magnet were used. When out of action the 

 two poles of the magnet would be supported either by a buffer 

 spring or by a steelyard weight, so that a distance not exceeding an 

 inch would exist between the poles of the magnet and the tram rail. 

 In the tender of the engine should be carried a voltaic battery, from 

 one pole of which should proceed a series of connectable chains 

 which should link each electro- magnet to the next throughout the 

 whole line, one end of the chains now made continuous being brought 

 to the battery to be connected with the opposite pole whenever 

 desired. Above the battery should be placed an electric dial and 

 connecting handle for the use of the driver, so as to enable him at 

 any moment to close or break the circuit, or so graduate it as to 

 permit him to govern the connection between any number of plates ; 

 ih other words, so as to enable him to govern the force of the current 

 as well as its connection and disconnection." 



Dr. Richardson did not say that his plan should replace the present 

 breaks in use ; these might be continued, but they could never per- 

 form all the important offices of the electro-magnet placed as above 

 described. Its advantages were — 1, It would at all times be at the 

 command of the driver of the engine ; 2, its action would be instan- 

 taneous ; 3, its action would be capable of gradation in arresting the 

 momentum ; 4, it would impede the motion of the carriage, not by 

 friction on the rail, but by adhesion with the rail— tiie arresting 

 force would thus be brought to bear on all points — the carriage 

 being for the under-current made essentially part and parcel of tire 

 line; 5, the force of adhesion being exerted through a line of car- 

 riages would double with the action of each magnet, and becoming 

 cumulative would increase in proportion to the length of the train, 

 bo that within a certain range, which experiment could Boon deter- 

 mine, the Bame battery force would answer for all trains whether 

 long or short ; 6, the magnets being brought to their arresturo in 

 any given case of accident, the overturn of the carriages by the 

 escape of it from the rail would be to a considerable extent pre- 

 vented ; 7, in eases where from fear of collision <>r other circum- 

 stances, the driver is compelled at all risks to stop in the briefest 

 time, the electro- magnetic break would so act thai every carriage 

 would Btop with an equal resistance — collision of carriages would thus 

 evented, since each carriage would stop itself by a spark com- 

 municated from the engine to the whole moving mass. The expense 

 of this would depend upon I he kind of bat :< II 'y : and in addition to the 



uses he had enumerated, j>r. Richardson mentioned several others to 



