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THE HON. J. W. STRUTT ON THE THEORY OF RESONANCE. 
quite sufficient to establish a substantial agreement between theory and fact. It should 
be understood that those here presented are not favourable specimens selected out of a 
large number, but include, with one exception, all the measurements attempted. There 
are many kinds of bottles and jars, and among them some of the best resonators, which 
do not satisfy the fundamental condition on which our theory rests. The deductive 
treatment of the problem in such cases presents great difficulties of a different kind 
from any encountered in this paper. Until they are surmounted the class of resonators 
referred to are of no use for an exact comparison between theory and observation, though 
they may be of great service as aids to investigation in other directions. 
