32 SECTIONAL ADDRESSES. 
century. Mr. Bertrand Russell, following such ideas to their logical 
conclusion, says that 
‘ physical science is approaching the stage when it will be complete, 
and therefore uninteresting. Given the laws governing the motions 
of electrons and protons, the rest is merely geography—a collection of 
particular facts telling their distribution throughout some portion of 
the world’s history. The total number of facts of geography required to 
determine the world’s history is probably finite: theoretically, they 
could all be written down in a big book to be kept at Somerset House, 
with a calculating machine attached, which, by turning a handle, 
would enable the inquirer to find out the facts at other times than 
those recorded. It is difficult to imagine anything less interesting, or 
more different from the passionate delights of incomplete discovery.’ 
If such a state of things were to come about, experiment in chemistry 
would be unnecessary, since all facts could be deduced from certain 
general principles and from fundamental physical constants which would 
by then have been determined with great accuracy. Of course, no person 
believes that such conditions will ever be attained, and the passage 
quoted above is only a picturesque statement of the position that all 
science may, in the last degree, be considered as mechanics. Chemists, 
however, know that this is not how their science has advanced or is likely 
to advance. Chemistry 1s an experimental science, which progresses by 
the application of a definite discipline, obtaining conclusions by induction 
from the observed facts, and making use of deduction from a small number 
of well-tried hypotheses where required. Granting the theoretical 
possibility that atomic theory might become so perfect that the facts of 
the chemical structure of molecules might be deduced from a com- 
paratively limited mass of data, it would nevertheless remain true that 
the labour of such deduction would be beyond human powers, except in 
relatively simple cases. We can scarcely imagine the properties and 
synthesis of indigo being deduced from the internal structure of the 
atoms of carbon, nitrogen, oxygen, and hydrogen, although it is possibly 
true that the one is implicit in the other. Human intelligence is not 
equal to the task, nor does it seem likely to be so in the future. Chemistry 
must continue to go its own way, whilst making every use of the new 
physical conceptions as an aid in generalisation and as a means of 
co-ordinating facts. There need be no fear that it will cease to have a 
separate existence. 
Chemical science has been responsible for the introduction of a number 
of hypotheses which have survived to the present day, and it may be 
worth while to look at them for a moment, although they are familiar to 
all and attention has been directed to them by recent writers. The 
doctrine of atoms, as we all know, was not a chemical invention, but there 
is a vast difference between its use among Greek philosophers as a means 
of satisfying their desire to find a consistent explanation of the universe 
and its scientific application in the hands of Dalton as a means of explana- 
tion of the quantitative facts of chemical combination. There has been 
some discussion as to Dalton’s personal attitude on this question, but 
there can be no doubt that those who did most to establish the doctrine 
attached no metaphysical importance to it, but used it frankly as an 
