io8 Presidential Address 



on the subject of Life, and on the possibility of artificially 

 producing it or of formulating its origin, excited so wide- 

 spread an interest. The penultimate predecessor is Sir 

 William Ramsay, the chemist who presided over the British 

 Association in 1911 at Portsmouth and whose experiments 

 on the influence of radio-active bodies in promoting the 

 transformation of one element into others have been re- 

 ceived with varying degrees of caution. The nominated 

 successor spoken of is Professor Bateson, the biologist who 

 before the Birmingham Meeting was nominated, and who 

 at Birmingham was elected, to preside over the British 

 Association during its meeting in Australia, and who is a 

 well-known authority on heredity, especially from the 

 Mendelian point of view. 



Page 10 



The second law of Thermodynamics relates to the work- 

 ing power of heat, and asserts the fact that only bodies at 

 high temperature can be usefully employed as sources of 

 heat. A hydraulic analogy is roughly useful as a first 

 approximation: water at high level can be used to drive 

 machines and give power, but water at average or sea level 

 cannot be so used. Hydraulic working power, therefore, 

 depends on two things, the amount of available water, and 

 its head or height above zero level. So it is also with heat. 

 The work which, by a heat engine like a steam or gas or oil 

 engine, can be extracted from it depends upon its quantity 

 and upon its temperature above some practicable zero, say 

 the ordinary average temperature. Only in the impossible 

 case of the practical zero being the absolute zero a fear- 

 fully low temperature approximated to by skilled experi- 

 menters but not actually attained could all of any given 

 quantity of heat be utilised in the performance of work. 



And yet heat is a form of energy, and a form which is 

 liable to be generated as a bye-product during every kind 



