ALLEGED EFFECT OF FROST. 157 



Society, and afforded opportunities for observing the com- 

 plete absence of egotism in Joule's character. He, ignorant 

 of what was coming, was dining with Professor W. C. Wil- 

 liamson, other members of the Society being present, when 

 he first heard that he was to receive the Copley medal. He 

 frankly showed the gratification which he felt in the 

 congratulation and expressions of sympathy from his 

 friends ; at the same time it was clear that he accepted the 

 honour as evidence of the recognition of the importance of 

 the truth for which he had so long laboured rather than 

 any special merit of his own. 



The numerous short communications which Joule read 

 before the Society between 1869 and 1872 afforded the 

 members opportunities of appreciating the activity and 

 clearness of his mind, and his scientific resource, as well as 

 his facility and skill as an experimentalist. But these com- 

 munications, relating chiefly to the invention of improve- 

 ments in physical measuring instruments, undertaken for 

 his own satisfaction and amusement and published mainly to 

 interest the Society, were invariably accepted with apprecia- 

 tion, and afforded little evidence of Joule's more personal 

 character. The Society was, however, early in 1 871, to be 

 treated to the opportunity of witnessing Joule under circum- 

 stances such as had rarely, if ever, happened to him before. 

 The first occasion was that which called forth from Joule his. 

 three communications " On the Alleged Action of Cold 

 in Rendering Iron and Steel Brittle." 



The severe winter of 1870, memorable for the Siege of 

 Paris, having attracted attention to the increase of railway 

 fractures, induced numerous comments on the effect of 

 frost on the strength of iron and steel. Some of the 

 members of the Society had taken an interest in the subject, 



