ON THE UNCERTAINTY OF CONCLUSIONS. 
11 
found to be nearly independent of its relation to heat, elec¬ 
tricity, magnetism, etc., and so, in turn, each characteristic 
may be studied alone and equations are obtained in which 
the number of constants is comparatively small. It is only 
after this plan has been pretty thoroughly worked out that 
it becomes possible to investigate the interrelations of these 
various properties, which are often obscure and difficult of 
detection. Their discovery, however, especially one or two 
great generalizations pertaining to them, such as that of the 
conservation of energy, must be regarded as the grandest 
triumph of physical science. 
The science of physics is that which is most drawn upon 
in the formation of the so-called applied sciences. Wedded 
to mathematics as it is (and no amount of personal abuse on 
either side can ever furnish good reason for divorce), it be¬ 
comes the mother of engineering in all of its various forms, 
Through and by it the forces of nature have been directed- 
the elements have been subdued and some of them overcome, 
and man has made himself master of the world. Its mar¬ 
velous progress has, therefore, been observed by the people 
and is understood by them perhaps to a greater degree than 
that of any other science. The most eloquent orators and 
the ablest writers have employed their genius in sounding 
its praises. 
It is not too much to say that when intelligent people speak, 
in a general way, of the wonderful things which science has 
accomplished during the past half century, they have in 
mind, for the most part, the applications which have been 
made of discoveries in physical science. I think no one can 
justly question the assertion that of the several causes which 
have produced the splendid advances in the material inter¬ 
ests of the whole world during the nineteenth century, science 
has contributed far more liberally than all others. So re¬ 
markable have been her achievements that all the people 
have come to look upon her as being nearly if not quite in¬ 
fallible. A reputation of which the votaries of science may 
be proud has been established, but, at the same time, one 
