LOW-TEMPERATURE RESEARCHES 



the impulse which Davy himself received from Rum- 

 ford being passed on to his pupil Faraday. There is, 

 then, an intangible but none the less potent web of 

 association between the scientific work of Rumford 

 and some of the most important researches that were 

 conducted at the Royal Institution long years after 

 his death ; and one is led to feel that it was not merely 

 a coincidence that some of Faraday's most important 

 labors should have served to place on a firm footing the 

 thesis for which Rumford battled; and that Tyndall 

 should have been the first in his "beautiful book" 

 called Heat, a Mode of Motion, to give wide popular 

 announcement to the fact that at last the scientific 

 world had accepted the proposition which Rumford 

 had vainly demonstrated three-quarters of a century 

 before. 



This same web of association extends just as clearly 

 to the most important work which has been done at the 

 Royal Institution in the present generation, and which 

 is still being prosecuted there the work, namely, of 

 Professor James Dewar on the properties of matter at 

 excessively low temperatures. Indeed, this work is in 

 the clearest sense a direct continuation of researches 

 which Davy and Faraday inaugurated in 1823 and 

 which Faraday continued in 1844. In the former year 

 Faraday, acting on a suggestion of Davy's, performed 

 an experiment which resulted in the production of a 

 "clear yellow oil" which was presently proved to be 

 liquid chlorine. Now chlorine, in its pure state, had 

 previously been known (except in a forgotten experi- 

 ment of Northmore's) only as a gas. Its transmu- 

 tation into liquid form was therefore regarded as a very 



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