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TRANSACTIONS OF SECTION B.—PRESIDENTIAL ADDRESS, 42 
Section B.—CHEMISTRY. 
PRESIDENT OF THE SECTION: 
Proressor A. Sener, Pu.D., M.D., D.Sc. 
THURSDAY, SEPTEMBER 5. 
The President delivered the following Address :— 
Part I. 
Peruars there is no intellectual occupation which demands more of the faculty 
of, imagination than the pursuit of chemistry, and perhaps also there is none 
which responds more generously to the yearnings of the inquirer. 
The nature It is surely no commonplace occurrence that in experimental labora- 
and method ties day by day the mysterious recesses of Nature are disclosed and 
of Chemistry. facts previously quite unknown are brought to light. The late 
Sir Michael Foster, in his presidential address at the Dover meeting, 
said : ‘ Nature is ever making signs to us, she is ever whispering the beginnings 
of her secrets.’ The facts disclosed may have general importance, and neces- 
sitate at once changes in the general body of theory; and happily, also, they 
may at once find useful application in the hands of the technologist. Recent 
examples are the discoveries in radio-activity, which have found an important 
place as an aid to medical and surgical diagnosis and as a method of treatment, 
and have also led to the necessity of our revising one of the fundamental 
doctrines of the theory of chemistry—the indivisibility of atoms. But the facts 
disclosed may not be general or even seem important; they may appear isolated 
and to have no appreciable bearing on theory or practice—our journals are 
crowded with such—but he would be a bold man who would venture to predict 
that the future will not find use for them in both respects. To be the recipient 
of the confidences of Nature; to realise in all their virgin freshness new facts 
recognised as positive additions to knowledge, is certainly a great and wonderful 
privilege, one capable of inspiring enthusiasm as few other things can. 
While the method of discovery in chemistry may be described, generally, 
as inductive, still all the modes of inference which have come down to us 
from Aristotle, analogical, inductive and deductive, are freely made use of. A 
hypothesis is framed which is then tested, directly or indirectly, by observation 
and experiment. All the skill, all the resource the inquirer can command, is 
brought into his service; his work must be accurate; and with unqualified devo- 
tion to truth he abides by the result, and the hypothesis is established, and 
becomes part of the theory of science, or is rejected or modified. In framing 
or modifying hypotheses imagination is indispensable. It may be that the 
power of imagination is necessarily limited by what is previously in experience— 
that imagination cannot transcend experience; but it does not follow, therefore, 
that it cannot construct hypotheses capable of leading research. I take it 
that what imagination actually does is—it rearranges experience and puts it 
into new relations, and with each successive discovery it gains in material for 
this process. In this respect the framing of a hypothesis is like experimenting, 
wherein the operator brings matter and energy already existing in Nature inte 
