Dynamical Theory of Heat. 371 



because it was published in Liebig's Annalen ; and bad Mayer's 

 subsequent memoirs been published in the same way, I do not 

 think you would ever have ventured to provoke this controversy. 

 The contributions from which, in connexion with his first one, 

 Mayer's merit as a philosopher is to be inferred, were published 

 as separate essays at Heilbronn. To these essays you never refer, 

 and from your silence I charitably inferred your ignorance of their 

 contents. This, however, does not satisfy you. And yet if I 

 assume that you are acquainted with these memoirs, how am I 

 to reconcile your knowledge with your silence ? 



You have thought it necessary to refresh my memory on an- 

 other point which I should willingly have allowed to remain at 

 rest. " Prof. Tyndall," you say, " is most unfortunate in the 

 possession of a mental bias which often prevents him (as, for 

 instance, in the case of Rendu and Glacier-motion) from recogni- 

 zing the fact that the claims of individuals whom he supposes to 

 have been wronged* have, before his intervention, been fully ven- 

 tilated, discussed, and settled by the general award of scientific 

 men." This language, as applied to Mayer, can only spring 

 from ignorance ; and as regards Rendu, it would be wise in you 

 to remember that your opinions on this matter are not those of 

 the world. Even among your own countrymen there are persons 

 too just and too free to be warped by a misnamed patriotism, 

 who, in common with the great majority of its readers in other 

 lands, consider that in my work upon the Alps the claims of Rendu 

 have been for the first time fairly set forth. No man, however, can 

 be less persuaded of his own infallibility than I am of mine, and 

 I clearly see the possibility of my having greatly erred in my 

 writings upon glaciers. But I am willing at all events to bring 

 my deeds to the light, so that, whether good or evil, they may be 

 made manifest. I have now to request you to refer me to the 

 passages of my writings on Rendu and Glacier-motion which 

 establish the unfortunate mental bias you have ascribed to me. 



It may shorten our correspondence, by making reflexion the 

 precursor of expression, if I here assure you that it is my fixed 

 intention not to permit random assertions to stand in this dis- 

 cussion. What you have the hardihood to affirm, you certainly 

 must have the goodness to prove or the manliness to retract. I 

 ask your proof, then, of the assertion you have made regarding 

 Rendu and Glacier-motion. 



der Chemie und Pharmacie. It is to be found in vol. xlii. page 233 of 

 the Annalen under the title ' Bemerkungen liber die Krafte der unbelebten 

 Natur.' " (Mayer, Bemerkungen uber das mechanische Equivalent der 

 Wdrme. Heilbronn and Leipzig, 1851.) 



* I did not suppose Mayer to be wronged : I supposed simply that he. 

 had wronged himself by his method of publication. 



