u 



Prof. A. Battelli and Mr. L. Mafrri 



1 on 



Experiments with circle-shaped circuit of copper wire. Total 

 self-induction of circuit for T = 0*00000120, 9242 era. 

 Capacity of condenser = 3568 eras. 



T= — VLC=0-000001201. 

 v 



Explosive distance 5 ram. 



Number 

 of crder 

 of Plate. 



n. 



n' . 



D. 



D'. 



P- 



T. 



"{ 



134-5 



133 



4-011 

 4-863 



2-585 

 2-526 



15 

 15 



000(3001213 

 OO0OCO12O5 



79 { 



158 



157 



5-202 

 5-296 



0634 

 0-398 



29 

 31 



00C0001224 

 000001229 



80 [ 



122 



120 



2-580 

 2-521 



2-451 



0-854 



33 

 22 



0-000001220 

 0-000001232 



81 1 



143 



140 

 



2-347 



2-275 



5-378 

 5-212 



19 

 19 



0000001194 

 0000001205 



82 { 



74 



76 

 



1-818 

 1-742 



5-493 



5-438 



23 

 23 



0-000001189 

 0-000001197 



83 | 



162 



162 



2-966 

 2-893 



3-050 

 2-843 



39 

 37 



0-000001210 

 0000001221 



85 | 



153 



153 



3147 

 3080 



1-153 

 0-959 



28 

 26 



0-000001210 

 0-000001224 



Theoretical value 0-000001201. Mean value 0-000001212. 



From the tables above given it may be seen that even when 

 the difficulties of measurements are greatest the possible error 

 in evaluating the period will not reach 2 per cent.; whereas 

 for not very short periods a still greater accuracy may be 

 attained. We believe that in the actual state an accuracy 

 superior to that reached by us cannot be obtained, the reason 

 of which will be given below. 



Now in order to compare the experimental value with the 

 value of the period as derived from Thomson's theory, it was 

 necessary to obtain the values of the elements entering into 

 Thomson's formula, i. e. capacity, resistance, and self-induc- 

 tion of the discharge-circuit, with an accuracy not inferior 

 to that pointed out above. It is thus necessary to explain 

 briefly the method and the precautions used in measuring 

 those elements of the circuit. 



0. Capacity. Resistance, and Self-induction of Circuit. 



(a) Condenser. 



13. In order to know the capacity with due accuracy, as 

 well for measuring the period as for measuring the dis- 

 posable energy, which we had to determine when studying 



