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LXXXV11. Noteon Einstein s Law for Addition of Velocities, 

 By W. B. Morton, M.A., Queen's University, Bel/ad*. 



rpHE way in which the theory of Relativity has modified 

 J. the law of combination of velocities can be shown very 

 clearly by an obvious graphical method, and tbe curves bring 

 out one or two points of some interest. 



Take first velocities in the same line. Let u be the 

 velocity of the '* moving platform" as seen from the 

 "ground" and v the velocity of a point on the platform 

 measured by platform standards, the velocity of light being- 

 taken as unity. Then the velocity of the point as seen from 

 the ground is (u+ v)j(l + uv). 



Fig.. 1. 

 10 





u ^ — ^^^/^ 



•8 ^ y^ / 



6 yS / 



•4- / 



■2 



V 



¥ 



•5 J-0 



G 



ivino- n a ue 



finite 



value, we may 



]>lot this "resultant" 



against r. 



This is done on fig. 1, for w="2, *4, "G, '8, these 

 * Communicated bv the Author. 



