292 FltA GMENTS 



Here, however, are the titles of Mayer's papers, the 

 perusal of which will correct any error of judgment into 

 which I may have fallen regarding their author. " Be- 

 merknngen liber die Krafte der unbelebten Natur," Lie- 

 big's " AMiialen," 1842, Vol. 42, p. 231; "Die Organische 

 Bewegung in i lire in Zusammenhange mit dem Stoffwech- 

 sel," Heilbronn, 1845; "Beitrage zur Dynamik des Him- 

 rnels," Heilbronn, 1848; " Bemerknngen iiber das 

 Mechanische Equivalent der War me," Heilbronn, 1851. 



IN MEMORIAM. Dr. Julius Robert Mayer died at Heil- 

 broun on March 20, 1878, aged 63 years. It gives me 

 pleasure to reflect that the great position which he will for- 

 ever occupy in the annals of science was first virtually as- 

 signed to him in the foregoing discourse. He was subse- 

 quently chosen by acclamation a member of the French 

 Academy of Sciences; and he received from the Royal 

 Society the Copley medal its highest reward.* 



November, 1878. 



At the meeting of the British Association at Glasgow in 

 1876 that is to say, more than fourteen years after its 

 delivery and publication the foregoing lecture was made 

 the cloak for an unseemly personal attack by Professor 

 Tait. The anger which found this uncourteous vent dates 

 from 1863, f when it fell to my lot to maintain, in opposi- 

 tion to him and a more eminent colleague, the position 

 which in 1862 I had assigned to Dr. Mayer. In those days 

 Professor Tait denied to Mayer all origina'lity, and he has 

 since, I regret to say, never missed an opportunity, how- 

 ever small, of carping at Mayer's claims. The action of 

 the Academy of Sciences and of the Royal Society sum- 

 marily disposes of this detraction, to which its object, dur- 

 ing his lifetime, never vouchsafed either remonstrance 

 or reply. 



Some time ago Professor Tait published a volume of 

 lectures entitled "Recent Advances in Physical Science," 

 which I have reason to know has evoked an amount of cen- 

 sure far beyond that hitherto publicly expressed. Many 



*See "The Copley Medalist for 1871," p. 479. 



\ See " Philosophical Magazine " for this and the succeeding years. 



