1919.] The Sixth Indian Science Congress. . ev 
India this arises either from surface waterlogging or by the limitation of 
percolation brought about by the rise of the ground water. The effect of 
this on growth and root development is discussed and some recent results 
with Java indigo are described in detail. The wider aspects of drainage in- 
volve the employment of engineers and the construction of 
=" 
Some observations of the life-history of an erotylid breed- 
ing in Italian millet—By P. V. Isaac. 
Section of Physics and Mathematics. 
President :—Dr. D. N. Maui, B.A., F.R.S.E. 
Presidential Address. 
REcENT ADVANCES IN PHysics AND MATHEMATICS. 
I beg to thank you for the honour you have done me by 
ae hes to preside on this occasion. 
en it was intimated to me that the Committee had 
been pleased to ask me to preside over the Physical and 
entire field. I knew that the task would not be an easy one. 
But I had not realized that it would be such a difficult—prac- 
tically an impossible task. 
ing to speak on recent advances, I naturally re- 
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that the lead, so authoritatively given ranges in the present 
able position, then, for one was clear as to what had been achieved 
and one had a cheerful belief that the position was unassail- 
able. It is no longer sonow. The present position can only 
be described as bewildering. Physicists, at the time of Tait’s ex- 
w of time and space. They had also a perfect faith in 
mathematical symbols, so that the calculus was to them an 
unfailing instrument, if only it could be somehow brought to 
bear on physical problems, duly suggested however by experi- 
ments. All that is changed now. It seems in the present day 
that the learning and teaching of physical science 1s almost a 
udge at least 
in which ridicule is often heaped on “text books” and 
“‘ present-day teaching.” Things are, however, not so as 
