( 401 ) 
A 
B has a smaller value for the coils of higher order than for those 
of lower order. 
TABLE. EV. 
t k 
Coils: Mean deviation in Mean deviation in | Wen 
k 
minutes. minutes. | 
3A 526.5 | 
6.52 
8B 12.4 
6A | 337.5 | 
5.9 
6B 9.7 | 
QA | 410.3 | | 
| | < 
9B | | 13.5 | Dok 
12A | 186.1 | | 
| | | 4.78 
12B | | 8.15 | 
| | 
15A | 501.1 | 
3.94 
15B | | 32.3 
The explanation of this phenomenon we shall have to look for 
in the fact that for the coils of higher order the secondary turns 
are farther removed from the iron core than for those of lower order. 
On account of this, for the former coils many of the lines of force, 
originating from the iron and being closed curves, will cut the 
cylindric space in the secondary coil twice, in 2 opposite directions. 
So these curves of force are entirely without value for producing 
induced currents in the secondary. 
If the induction coils were arranged in such a way that the iron 
core formed a ring closed in itself, the above mentioned phenomenon 
could not take place, as then each line of force would cut the space 
in the secondary coil only in one direction. 
If we write down the values for 5 found according to the two 
