454 THE POPULAR SCIENCE MONTHLY 
of a single charged atom can be detected by electrical means. Thus the 
electroscope is millions of millions of times as sensitive as the spectro- 
scope, which is itself in many cases far more sensitive than the balance. 
This explains, in part, why radium was discovered by physicists, and why 
physicists have been most active in all the work which has had to do 
with the theories of electricity and matter. If chemists wish to com- 
pete with physicists in this field of investigation they must adopt phys- 
ical methods and apparatus, or devise some which shall be far more 
sensitive than the balance or spectroscope. Further, some of the great 
chemists of the world need to awake to the fact that there is something 
doing and that they are not doing it. The conservatism and indifference 
of some of them are surprising. But afew months ago one of them ex- 
pressed the following sentiments in a paper read before the Chemical 
Section of the British Association.® “.. . those who feel that the 
electron is possibly [note the possibly] but a figment of the imagination 
will remain satisfied with a symbolic system which has served us so 
long and so well as a means of giving expression to facts which we do 
not pretend to explain. . . . Until the credentials of the electron are 
placed on a higher plane of practical politics, until they are placed on 
a practical plane, we may well rest content with our present condition 
and admit frankly that our knowledge is insufficient to enable us even 
to venture on an explanation of valency.” Think of it! We, the chem- 
ists, “ remain content,” in this day when, as the Hon. A. J. Balfour has 
said, the attempt to unify physical science and nature’ “ excites feelings 
of the most acute intellectual gratification. The satisfaction it gives 
is almost esthetic in its intensity and quality. We feel the same sort of 
pleasurable shock as when from the crest of some melancholy pass we 
first see far below the sudden glory of plain, river and mountain.” 
“ Rest content!” No wonder the Nobel prize in chemistry was awarded 
to Rutherford, a physicist. 
As to the second principle, the conservation of energy, some have 
had misgivings. It was Kelvin, I believe, who said that radium placed 
the first question mark after this great principle. Many have refused 
to believe in the electron and disintegration theories because they saw, 
or thought they saw, in these theories a contradiction of the principle 
of energy conservation. Personally I do not see that there are neces- 
sarily any contradictions. But even if there were and we were there- 
fore justified in rejecting the theories proposed to explain the facts, we 
certainly should not be justified in rejecting the facts themselves. 
In this connection I am reminded of the story of a lawyer whose 
client was placed in jail for some very trivial offence. When the 
lawver learned the nature of the charge he said to his client: “ My 
‘s Scientific American Supplement, 63, No. 1761, p. 210, October 2, 1909. 
7 Reflections Suggested by the New Theory of Matter,” presidential ad- 
dress, British Association for the Advancement of Science, 1904. Science, 20, 
No. 504, pp. 257-266, August 26, 1904. 
