HELMHOLTZ ON PRIORITY QUARRELS 217 



had not found that any substantially new arguments had been brought forward by 

 his opponents 1 ." 



At the end of a long letter of date 27 March, 1867, mainly occupied 

 with a discussion of his and Stewart's experiments on the rotating disk in 

 vacuo, Tait asked Helmholtz : 



Is it fair to ask you whether you think with Clausius that my little pamphlet 

 will only do me harm or with Thomson and Joule (who, of course, are interested 

 parties) as well as Stewart, who have reported favourably on it ? I wish to avoid 

 strife and to produce a useful little text-book ; but, if Clausius is right, I had better 

 burn it at once. 



In his reply of April 30, 1867, Helmholtz considered some of the 

 difficulties in the proposed experiments on the rotating disk, then thanked 

 Tait for his offer to publish his translation of the paper on " Vortex Motion," 

 and finished with the following wise words : 



" In regard to the question of the publication of your sketch of the history of 

 the mechanical theory of heat it is very difficult to give advice. For my part I 

 must say that I have a great aversion to all priority quarrels and have indeed never 

 myself protested against the greatest misappropriation (eingriffe) ; and I find that I 

 have in this way really come well off, and that in the end my Own has been 

 adjudged again. But I know that my best friends think differently on this matter, 

 and that I stand pretty much alone in my opinion. Further as regards the services 

 of Joule and Thomson in the matter under discussion they appear to me to be so 

 completely and generally recognised by all intelligent people with whom I have 

 spoken that a polemic in their interests is hardly needed. 



" If then you divest your writing of its polemical garb it will in my opinion be 

 thankfully received and will have more influence than with this polemic. 



"This is my opinion, since you have wished to hear it; naturally I shall not 

 take it ill if you do not follow it, since I do not know enough of the personal 

 conditions which may be moving you." 



Tait however thought otherwise, and in the interests of his friends and 

 for what he regarded as the truth he sent forth his book in all its individuality. 



The general character of the three chapters may be inferred from their 

 titles, namely, (i) Historical Sketch of the Dynamical Theory of Heat, 

 (ii) Historical Sketch of the Science of Energy, (iii) Sketch of the Funda- 

 mental Principles of Thermodynamics. The book opens with the arresting 

 question, What is Heat ? The gradual undermining of the old Caloric Theory 



1 It may be remarked here that Lord Rayleigh, in his paper "On Balfour Stewart's 

 Theory of the Connexion between Radiation and Absorption" (Phil. Mag., Jan. 1901), agrees 

 with Tait that Stewart had made out his case. 



T. '8 



