75 



tion can be ascertained from the table. 

 If, for instance, the induction in the 

 small transformer is 8,000, that in the 

 large one may be taken as 5,000, and the 



electromotive force will be ' X 4 = 



o,UUU 



2.5 times that of the small transformer, the 

 output being increased in the ratio of 1 

 to 2.82 x 2.5 = 7 about. It should 

 also be observed that the larger appa- 

 ratus will, in so far, be more advantageous, 

 as a smaller proportion of space will be 

 occupied by insulation, especially if both 

 are required for the same circuit. The 

 ratio of output may thus be increased 

 from seven to eight, or ten, or even more, 

 according to the size of transformer 

 taken as the basis of the comparison. 

 For larger sizes, the advantage resulting 

 from an increase of linear dimensions 

 will be less apparent, and the output may 

 roughly be taken as proportional to the 

 weight. 



The question of frequency, alluded to 

 in connection with alternators, is also of 

 considerable practical importance with 



