COFFIN. — THE SELF-INDUCTANCE OF COILS. 709 



PLOT I. 



1.0 



0.9 



o.s SB 



0.7 



0.6 



0.5 



0.4 



0.3 



0.2 



0.1 



0.0 



3 



x = 1 5 



Plot of the functions Q = 



4 5 6 7 



3 sinh x — sin x 



x cosh x — cos x 



full line. 



10 11 12 13 14 15 



Q 1 =(l — x\ 630) dotted line. 

 Q 2 — Z\x dotted line. 



