January 3, 1908] 



SCIENCE 



"It was very pleasant and informal. W. 

 Thomson has carried the freedom of inter- 

 course so far that he always carries a 

 mathematical note-book about with him, 

 and as soon as an idea occurs to him, 

 begins to reckon right in the midst of the 

 company, which is generally regarded with 

 a certain awe. How would it be if I 

 should accustom the Berliners to that?" 

 On the occasion of a visit in Glasgow he 

 writes, ' ' He has no vacation at Easter, but 

 his brother James, professor of engineering 

 at Belfast, and a nephew, are there. The 

 former is a very clever head with good 

 ideas, but hears and knows nothing but 

 engineering, and speaks of it continuously 

 at all times of the day and night, so that 

 hardly any conversation can take place 

 when he is there. It is funny, too, how 

 each of the brothers explains something to 

 the other, and neither listens to the other, 

 and each talks of totally different subjects. 

 But the engineer is the most obstinate of 

 the two and generally puts his piece 

 through." The friendship between these 

 two great physicists, Helmholtz and Thom- 

 son, both without other peers, was most in- 

 teresting from the fact that they many 

 times almost simultaneously treated the 

 same subjects, and that they were both 

 examples of Helmholtz 's statement that 

 "in physical science he only can fruitfully 

 experiment who has a penetrating knowl- 

 edge of theory and according thereto can 

 ask the right questions, and on the other 

 hand, as is most brilliantly shown in the 

 discovery of spectrum analysis, he only can 

 fruitfully theorize who has a broad 

 practical experience in experimentation." 

 Would that these words and these examples 

 might be carved in letters of gold in every 

 laboratory in this land! 



The honors heaped upon Thomson would 

 fill a catalogue. Knighted in 1866, he is 

 most familiarly known as Sir William 

 Thomson, elected foreign associate of the 



Paris Academy of Sciences in 1877, he 

 was raised to the peerage by Lord Salis- 

 bury in 1892, taking the title of Baron 

 Kelvin, from the stream on which Glas- 

 gow is situated. He was president of the 

 Royal Society, four times president of the 

 Royal Society of Edinburgh, and member 

 of nearly all the learned societies of the 

 world. He was one of the twenty members 

 of the recently instituted Order of Merit, 

 of which the other scientific members are 

 Lord Rayleigh, Sir William Huggins and 

 Lord Lister. On his third visit to this 

 country, in 1902, he was tendered by several 

 scientific societies a great reception at Co- 

 lumbia University, where his praises were 

 sung before a distinguished company. His 

 visit to the American Physical Society 

 was a memorable one for that society, of 

 which he was the first honorary member. 

 Kelvin's printed works comprise one vol- 

 ume of "Papers on Electrostatics and 

 Magnetism," three volumes of "Mathe- 

 matical and Physical Papers" (those not 

 yet published will make another) , Thomson 

 and Tait's "Treatise in Natural Philos- 

 ophy," in two volumes, and three volumes of 

 Popular Lectures and Addresses. Of these 

 many papers the majority are not of an 

 experimental character, and Kelvin's ex- 

 perimental work that will be best remem- 

 bered is probably comprised in his dis- 

 covery of the Joule- Thomson cooling effect 

 in gases and of the Thomson effect of the 

 carriage of heat with or against the electric 

 current. 



Kelvin's great strength consisted in his 

 mastery of the application of mathematical 

 methods, and of mechanics in particular, 

 combined with his rare physical intuition 

 and his ability to construct models to make 

 difficult phenomena tangibly realizable. 

 Helmholtz says of him in his preface to his 

 translation of Thomson and Tait, "William 

 Thomson, one of the most penetrating and 

 ingenious thinkers, deserves the thanks of 



