.264 Prof. Tait on the Claims of Mayer and Joule. 



Tyndall' s lecture was an article in ' Macmillan's Magazine ' 

 (August 186.2), which found publicity in the peculiar society of 

 " Water Babies," " Sunken Rocks," and " Women of Italy/' 



When I first saw Prof. TyndalPs lecture, I happened to be in 

 Arrari with Prof. Thomson ; and, as he had been repeatedly asked 

 by the Editor of ( Good Words ' to contribute a scientific article 

 to its columns, we seized the opportunity of distributing among 

 its 120,000 readers a corrective to the erroneous information 

 which we saw was stealing upon them through the medium of 

 popular journals. 



Second, as to our knowledge of what Mayer has done, which 

 Prof. Tyndall allows may now be more complete than when our 

 article was written. If Prof. Tyndall will refer to vol. xx. p. 262, 

 of the Transactions of the Royal Society of Edinburgh (or to the 

 Philosophical Magazine, 1852, second half-year, p. 9), where the 

 paper is reprinted), he will find that so long ago as 1851 Prof, 

 Thomson at least was well acquainted with Mayer's first paper, and 

 had given him the full credit that his scientific claims can possibly 

 be admitted to deserve. Prof. Tyndall 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 recog- 

 nizing the fact that claims of individuals whom he supposes to 

 have been wronged have, before his intervention, been fully 

 ventilated, discussed, and settled by the general award of 

 scientific men. 



So much for our ignorance of Mayer, our putting two pens 

 to a paper instead of one, and our choice of a popular monthly 

 magazine as a channel for publication. 



Does Prof. Tyndall know that Mayer's paper has no claims to 

 novelty or correctness at all, saving this, that by a lucky chance 

 he got an approximation to a true result from an utterly false 

 analogy; and that even on this point he had been anticipated 

 by Seguin, who, three years before the appearance of Mayer's 

 paper, had obtained and published the same numerical result 

 from the same hypothesis ? Prof. Tyndall has quoted, without 

 comment, our note on the subject. Does he recognize the truth 

 of that note ? If he does not, let him expose its errors ; and we 

 shall be happy to acknowledge our mistake, and to hail the 

 additions to scientific knowledge which (involving at least a 

 reconstruction, if not a destruction, of thermo-dynamics) must 

 result from Mayer's statement if it can be shown to be true. 



As to the passage in our paper which seems to have especially 

 displeased Prof. Tyndall, I think it sufficient to make the fol- 

 lowing remarks : — 



Let Prof. Tyndall speak for himself. In his lecture he says, 

 "To whom, then, are we indebted for the striking generaliza- 



