"MATHEMATICS AND CHEMISTRY": A REPLY 395 



action are considered as well as the more complicated examples 

 but it is also made quite clear that " there are cases in which n as 

 derived from velocity measurements does not agree with that 

 derived from the chemical equations " (p. 150), which apparently 

 is what Mr. Worley is telling us on p. 410 ; and further on more 

 space than usual is devoted to emphasising the uncertainty 

 which always attaches to the determination of the " order " of an 

 interaction by means of velocity measurements : " The view is 

 becoming more and more pronounced that reactions of higher 

 orders are very rare" (p. 152); "a chemical reaction is the re- 

 sultant of a large number of conditioning causes . . . and 

 therefore proceeds in a variety of ways and leads to a variety of 

 products. It is only in a few cases that we can say exactly how 

 a reaction proceeds in all its stages " (p. 246). I had hoped that 

 this would not have given rise to the opinion that there was any 

 attempt to make out that the whole matter is really simpler than 

 is actually the case and should have thought that it would have 

 been unnecessary for my critic to say that " the law of mass action 

 is a generalisation of an axiomatic nature, never apparently 

 obeyed exactly and incapable therefore of absolute proof; that 

 even if the correct assumptions are made with regard to the 

 number and nature of the interacting molecules there are many 

 disturbing factors, as a rule, that cannot be taken into account " 

 (p. 408). It would be interesting in the light of his statement 

 that the law of mass action is " a generalisation of an axiomatic 

 nature," to ask the author if he knows the difference between a 

 generalisation and an axiom, as exemplified by the Second 

 Law of Thermodynamics and if he has ever heard of Willard 

 Gibb's thermodynamic demonstration of the law of mass action. 

 After what had been said on the tendency to superficiality 

 exhibited by existing text-books, it is not surprising to find the 

 author stating that " it is consequently highly desirable that the 

 mathematical treatment of a question, such, for instance, as that 

 of mass action, should be thorough, dealing with all the 

 difficulties that arise." One is tempted to ask if the writer has 

 found this method possible in practical teaching ? 



Mr. Worley has also introduced some remarks on the theory 

 of solution into his paper. After exciting our imagination by a 

 moving picture in which a high edifice of " mathematical 

 jugglery " is to be " razed to the ground," he makes us " shudder 

 to think of the terrific downfall should the foundations give 



