Manchester Memoirs, Vol. Iv. (191 1). No. 3?i. 5 



Though Davy saw fit afterwards to qualify this 

 declaration, he could never undo the effect it produced. 

 No one was better able than he to make Higgins known 

 at once, for he was famous throughout Europe. His 

 papers were read by all scientific men : thus Berzelius 

 and Arago each mention that their attention was drawn 

 to Higgins by Davy. The consequence in this country 

 was a long and desultory controversy regarding the 

 respective claims to the atomic theory of William Higgins 

 and John Dalton. 



In the course of the controversy the suggestion was 

 made that Dalton had been guilty of plagiarism at the 

 expense of Higgins. The charge was made far too 

 lightly.* Dalton was not a great reader, and it was very 

 unlikely he would look twice at a book which dealt, on 

 the face of it, expressly with the phlogiston controversy. 

 But it was necessary that a statement on the subject 

 should be made, and the statement was forthcoming. 

 Thomas Thomson declared that Dalton had no knowledge 

 of Higgins' book previous to the year 18 10, and this 

 declaration was made repeatedly afterwards by Dalton's 

 personal friends.^ 



It is easy to account for the resemblance between the 

 two theories. They had a common origin in Newton's 

 ideas, and there is no need for any other explanation. 



■* Du Eois Reymond and Helmholtz each hit upon the same illustration 

 of the time taken by a nervous impulse. "A whale probably feels a wound 

 near its tail in about a second, and requires another second to send back 

 orders to the tail to defend itself." " Hermann von Helmholtz," by von 

 Koenigsberger, Eng. trans., 1906, p. 72. 



^ Thomson, Annals of Phil., 4, 54, 18 14 ; William Henry, " Elements 

 of Experimental Chemistry," nth ed., 1829, i, 45; W. C. Henry, 

 "Memoirs of Dalton," pp. 78, 175, 217. 



