SECTION A.—MATHEMATICAL AND PHYSICAL SCIENCES. 
THE GROWTH IN OPPORTUNITIES 
FOR EDUCATION AND RESEARCH 
IN PHYSICS DURING THE PAST 
: FIFTY YEARS 
ADDRESS BY 
SIR J. J. THOMSON, O.M., Sc.D., D.Sc., LL.D., F.R.S., 
PRESIDENT OF THE SECTION. 
Durine the last year we have lost by the death of Prot. Albert Michelson 
a physicist whose work was of quite exceptional importance. The famous 
experiment known everywhere as the Michelson-Morley experiment has, 
since it is the basis of the Theory of Relativity, been largely responsible 
for the trend of physical thought during the present century. It is a 
very striking example of the great philosophical consequences which can 
_ result from what might seem the rather mechanical process of improving 
the precision of physical measurements ; the importance of the experiment 
depended entirely on the accuracy of the measurements being great 
enough to detect with certainty changes amounting only to one part in a 
hundred million. 
The additions to our knowledge of physical phenomena and the 
number of new ideas introduced into Physics since the last Anniversary 
_ Meeting have been so great and cover such a wide range that it would 
be impossible in the time at our disposal to give an account of them 
which would be at all adequate or even intelligible to those not 
already acquainted with them. There are, however, advances of another 
kind of great importance to the progress of Physics which lend themselves 
more readily to a less inadequate treatment in such an address as this. 
Such advances are the increase in the opportunities for teaching and re- 
search in Physics caused by the foundation of many new laboratories, the 
increase in the attention paid to the teaching of Physics in our schools, the 
endowment of research workers and the increase in the opportunities for 
these to obtain remunerative employment, the increased recognition of 
the importance of research in industry, and last but not least the improve- 
ments made in instruments used in research and the increase in the 
magnitude of the forces, mechanical, electric and magnetic, which are now 
at our disposal. The Physical Laboratories in the eighteenth century 
and the first half of the nineteenth were in the main collections of 
instruments suitable for experiments to illustrate the lectures of the 
Professor, and the trouble taken over these experiments was, I think, 
comparable with that taken now. Thus, Wollaston, who was Jacksonian 
_ Professor at Cambridge at the end of the eighteenth century, is said to 
‘ c2 
