418 Mr. R. H. M. Bosanquet on the Determination 



Data for this last formula : — 



n= 1000 n'= 250 



a=27*056 a'=26*512 



#=7*925 

 2/i = 2-18 2A' = -562 



2&=5*45 2^ = 5-77 



Coefficients of Induction of 42 araZ 250 cot7s. 



Distance between central planes, 6 = 6*35 centim. 

 /3 by half turn of 1000 coil, in S, throughout. 



Date. 



Set. 



Arranger 

 ment. 



a. 



(3. 



e. 



Galvano- 

 meter. 



Make & break 

 or reversal. 



M. 



Feb. 23. 



1 



42 P 



250 S 



202-2 



142 



3156' 



2 



m. b. 



10 6 x 5-9390 





2 



250 P 



42 S 



88-2 



173 



4420 



18 



rev. 



X 6-1075 



Feb. 24. 



1 





86-5 



175 



43 55-5 







X 6-0030 





2 





85-2 



175 



43 5 







X 60893 





3 



42 P 



250 S 



190-2 



144-7 



29 43 



2 



m. b. 



X 5-9862 



c 



alcu 



lation b 



y Ma: 



«:well\ 



3 origin 



al formi 



ila . 10 6 



x 5-275 



Comparison of arrangements : — 



42 P 250 P 



250 S 42 S 



Feb. 23. 1 10 6 x 5*9390 Feb. 23. 2 



„ 24. 3 x 5-9862 „ 24. 1 



2 



Mean x 5*9626 



10 6 x 6-1075 

 x 6-0030 

 x 6-0893 



Mean x 6-0666 

 Mean of both arrangements 10 6 x 6'0146. 



Feb. 24. 



Determinations of Coefficient of Induction of Dynamo Field- 

 magnets and Armature. (A Gramme.) 



P field-magnets, with two bichromates and 10 



B.A. units. 

 S armature, ballistic galvanometer, and 1000 coil. 

 By reversal. 



G-alvano- 

 /3. 9. meter. Amperes, 



179' 27° 11' 18 *181 



Mean value . 

 Highest value 

 Lowest „ 



a. 



146' 

 176 

 113 



M. 

 10 7 xl85 

 x2- 

 <1*43 



