134 



Trans. Acad. Sci. of St. Louis. 



then independently the characteristic of the dynamo was 

 obtained — fig. 10. 



The line A'B 2 of figs. 10 and 18 will then give the counter 

 e. m. f . that the motor must develop. This line was there- 



4 6 8 10 12 



Fig. 19 

 Series Motor Test. Comparison of Observed and Computed Kesults. 



fore projected onto the motor surface and the line on the sur- 

 face was projected onto the ni plane giving the relation 

 between speed and current to be expected when the motor 

 was driven by the generator. This is seen in fig. 18 and en- 

 larged is the full line of fig. 19. The motor was then driven 

 by the generator and the indicated points of fig. 19 give the 

 result. 



