ATOMIC THEORY. 399 



must have been the contrast between him and Dalton ; the 

 latter what we have already described him the former 

 equally placid in demeanour, but with the air, habits, and 

 courtesies of an old French nobleman. In estimating their 

 relative genius we must needs rank Laplace far above the 

 level of Dalton. Both of them mathematicians, they yet 

 trod in mathematical paths so remote from each other as 

 almost to efface every vestige of this connection. The very 

 diversity here is the exponent of the scientific character of 

 the two men. Dalton may be said to have worked in straight 

 lines, both in mathematics and general physics ; with definite 

 objects placed clearly before his conceptions, which he 

 pursued steadily by the simplest or even rudest methods, 

 to the attainment of the results desired. The genius of 

 Laplace took for its sphere of action the wide domain of the 

 universe : and while by the mighty power of his analysis he 

 was removing anomalies, and reconciling even the secular 

 perturbations of the planets to the one great law of gravita- 

 tion, he applied the same power and the same methods of 

 evidence to almost every part of human knowledge. He 

 worked not in straight lines but sweeping over a vast circle, 

 and bringing each part into relation with the whole. 



It is difficult to give any single definition of genius, having 

 due regard to the endless varieties and anomalies which pre- 

 sent themselves in the human intellect. In the higher ac- 

 ceptation of the term, Dalton could hardly be called a man 

 of genius. He had not those wings with which some men 

 soar over the ocean of undiscovered truth, discovering regions 

 to be submitted hereafter to human intelligence and power. 

 But he brought to his researches, as we have seen, the habits 

 of a sagacious and intrepid thinker ; swayed by no authority 

 but that of facts, and sedulous in seeking for these by his own 

 labours and methods. We believe this description to include 

 all that is most peculiar in his character as a philosopher. 



