SCIENC& 



you see, or dream, or in any way imagine, how out of 

 that mechanical act, and from these individually dead 

 atoms, sensation, thought, and emotion are to rise ? 

 Are you likely to extract Homer out of the rattling of 

 dice, or the Differential Calculus out of the clash of 

 billiard balls? ... I can follow a particle of musk 

 until it reaches the olfactory nerve ; I can follow the 

 waves of sound until their tremors reach the water of 

 the labyrinth, and set the otoliths and Corti's fibres in 

 motion ; I can also visualise the waves of ether as they 

 cross the eye and hit the retina. Nay, more, I am able 

 to pursue to the central organ the motion thus imparted 

 at the periphery, and to see in idea the very molecules 

 of the brain thrown into tremors. My insight is not 

 baffled by these physical processes. What baffles and 

 bewilders me is the notion that from these physical 

 tremors things so utterly incongruous with them as 

 sensation, thought, and emotion can be derived.' It is 

 only a complete misapprehension of our true relation- 

 ship that could induce Mr. Martineau to represent Du 

 Bois-Keymond and myself as opposed to each other. 



* The affluence of illustration,' writes an able and 

 sympathetic reviewer of this essay, in the ' New York 

 Tribune,' ' in which Mr. Martiueau delights often 

 impairs the distinctness of his statements by diverting 

 the attention of the reader from the essential points of 

 his discussion to the beauty of his imagery, and thus 

 diminishes their power of conviction.' To the beauties 

 here referred to I bear willing testimony; but the 

 reviewer is strictly just in his estimate of their effect 

 upon my critic's logic. The * affluence of illustration,' 

 and the heat, and haze, and haste, generated by its 

 reaction upon Mr. Martineau's own mind, often pro- 

 duce vagueness where precision is the one thing needful 

 poetic fervour where we require judicial calm ; and 



