Arthur Riicker, John Poynting 161 



positions he gave up when he accepted the Principalship 

 of London University in 1901. 



John Poynting was the first Professor of Physics at 

 Mason College (now the University), Birmingham. He was 

 brought up in Manchester, and obtained his first instructiori 

 in Physics from Balfour Stewart. In due course he went 

 to Cambridge, graduated as third wrangler, and was elected 

 to a Fellowship at Trinity College in 1878. For a time he 

 worked in the Cavendish Laboratory, and in 1880 went to 

 Birmingham, where he remained until his death. Poynting 

 belonged to the rare type of men who are more critical of their 

 own work than of that produced by others. The number 

 of his papers is therefore comparatively small, but each 

 of them marks some definite and generally important step. 

 He broke new ground when he investigated the path along 

 which energy may be considered to be propagated in an 

 electromagnetic field, and the vector, by means of which he 

 represented the magnitude and direction of the transmitted 

 energy, has proved to be a fruitful conception. His in- 

 vestigations on the " pressure of light " have also led to 

 many interesting consequences, which are likely to gain 

 considerable importance in questions connected with the 

 constitution of the sun and stars. In another series of 

 experiments he attacked the difficult problem of gravitational 

 attraction and showed how an apparently unpromising 

 method may be skilfully applied so as to give valuable 

 results. 



Turning to the share of non-academic workers in the 

 recent progress of science, it is not surprising that it tends to 

 become less prominent, various reasons combining to render 

 it more and more difficult for the so-called amateurs to hold 

 their own. It is now generally only in those subjects which, 

 in consequence of great specialization, have become almost 

 entirely self-contained, that a man who is unable to devote 

 his whole time to study can hope to produce original work 

 of high quality. The most effectual of the contributing 

 causes has, however, probably been the growth of the 

 universities and their emancipation from the narrow ideas 

 of the Middle Ages. There is a university within the reach 

 of nearly everyone and men are drawn into the academic 



L 



