FT. n. Mr. Darwin and Mr. Suckle. 59 



ture of dogmatism or intolerance of opposite views ; 

 he has a profound conviction of the soundness of 

 his own theories, and invites all adverse criticism 

 with philosophical calmness and with a strong con- 

 fidence in the justice of his own system. It is due 

 both to his high authority and to the tone in which 

 he places his doctrines before us to consider them 

 in the same spirit of impartiality and moderation. 

 He invokes the judgment of our reason, and even 

 should that judgment be adverse to all our pre- 

 conceived opinions he has a right to claim it. 



The march of true Science is irresistible ; wherever 

 her foot is once planted it can never be withdrawn 

 she is the mightiest of conquerors. Everything 

 must give way before her ; however unwilling or 

 reluctant mankind may be, they have no choice but 

 to follow wherever she has once taken an authorita- 

 tive lead. Just as bows and arrows have given place 

 to muskets, and brown bess to breech-loaders, the 

 old sailing vessels to screw steamers, and the screw 

 steamers to iron clads, so in every other path, when- 

 ever it is once clearly and fully illumined by the 

 torch of Science, the human race have no choice 

 but to follow. If fifty years ago any speculative 

 chemist had foretold the possibility that by a com- 



