KELVIN 191 



Lord Kelvin was hearty and genial, and generally 

 wore a winning smile ; and he was the most modest of 

 great men. 



On one occasion he paid a visit with a friend to some well-known 

 electrical works. They were escorted over the workshops by the senior 

 foreman, a man of much intelligence and an enthusiastic electrician. 

 Entirely unaware of his visitor's identity, he minutely explained the 

 details of the plant and machinery, and lectured him in his r61e of 

 layman quite professionally. Lord Kelvin's friend was on the point of 

 interrupting several times, but an amused signal from the great master 

 of electricity kept him silent. When the tour of inspection was com- 

 plete, Lord Kelvin quietly turned to the foreman and asked, "What, 

 then, is electricity?" This was a poser for the man, who, somewhat 

 shamefacedly, confessed that he could not say. " Well, well," said Lord 

 Kelvin gently, " that is the only thing about electricity which you and 

 I do not know." 



Lord Kelvin was the greatest teacher of physics of his 

 day, but his lectures were never simple; in fact, his 

 "popular addresses" were more suitable for wranglers 

 than anybody else. His subjects were so simple to him 

 that he frequently overlooked the fact that he took his 

 audience clean out of their depth. He was essentially a 

 teacher of teachers. 



In 1896 Lord Kelvin celebrated the jubilee of his 

 professorship at the Glasgow University, and on this 

 occasion men of science from all parts of the world did 

 honour to the great physicist ; and he was presented 

 with the Arago gold medal by the Acade*mie des Sciences. 

 Numerous addresses were presented to him from the 

 various universities, academies, and societies of the world, 



