( 367 ) 



03 



-a 



a 

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ca 



T3 



lu 



PQ 



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been formeel as shown in Table II ; in these series irregularities still 

 occur, but by far the greater part have disappeared and they furnish 

 good material for the application and the testing of frequency-formulae. 

 For this purpose two alterations have to be made : in the first 

 place the scale value has to be altered so that the extreme limits are 

 denoted, not by and 10, but by ± 1, and consequently the origin 

 of coordinates must be chosen in the middle between the limits ; 



