9 
There are two main factors which science teaches: one, that 
we must always be prepared to review our theories and doctrines 
in the light of new discoveries and new data, for there is no 
finality to scientific knowledge. The scientific beliefs of one gen- 
eration have frequently been abandoned by succeeding genera- 
tions, because their observation and data have been based on the 
apparent and from insufficient knowledge has failed to point the real 
factors. I jack of observation instruments prevented early investi- 
gators from analysing and proving their theories, and even in the 
present day doubt lias been thrown on the existing assumption that 
light travels through space in a straight line uneffected by gravita- 
tion as of the sun, and it is expected that (he solar eclipse of last 
month will decide this question. 
We are liable to come to wrong conclusions if we only observe 
an • occurrence from one point of view. How often do we notice 
when travelling fast in a railway carriage that the sparks from 
the engine appear- to rush past; in a nearly horizontal streak 
it is hard to realise that the appearance of the fiery track is due 
entirely to our rushing past the slowly falling sparks, whereas a 
person watching the passing train would notice that the sparks are 
slowly falling vertically to the ground. This simple illustration 
should teach us to consider both sides of the story before we come 
to a conclusion. 
Science teaches us that the more we know the more there is 
to learn, and every new discovery opens a field for further investi- 
gation. If 1 may be permitted to use a simile, take two circles-, 
one small and the other large, and take the area of each circle to 
represent the extent of knowledge in each case and let the cir- 
cumference be called the horizon of ignorance, and you will see 
that as the area of knowledge increases so does the horizon of 
ignorance increase. 
Adam Gowan White, says of knowledge: “Truth is nothing 
more than the essence of organised knowledge.” This expression 
grows and alters as knowledge grows and alters; it is dynamic, not 
static. 
1 have i apidly and in a very fragmentary manner referred 
to some of the phases in the history of science and its influence on 
civilisation, but with such a vast subject it is impossible to 
deal with it adequately in one evening. 
There are one or two modern phases, however, to which I 
would like to allude. For some years before the War, Germany was 
recognised as one of the foremost, if not the foremost, nation in 
the encouragement of science and in the employment of scientific 
works in her industries. 
Her scientific workers had gained for her practically a world- 
wide monopoly, especially in aniline dyes and also in many other 
chemical industries, and this was largely due to their research 
