MAN THE INTERPRETER OF NATURE. 205 



four miles of blank paper which rolls off the cylinder at one end, 

 being delivered at the other, without any intermediate human 

 agency, as separate Times newspapers, at the rate of 15,000 an 

 hour. Now what is the cai/se of this most marvellous effect? 

 Surely it lies essentially in the power or force which the pulling of 

 the handle brought to bear on the machine from some extraneous 

 source of power, — which we in this instance know to be a steam- 

 engine on the other side of the wall. This force it is, which, dis- 

 tributed through the various parts of the mechanism, really performs 

 the action of which each is the instrument; ihey only supply the 

 vehicle for its transmission and application. The man comes 

 again, pushes the handle in the opposite direction, detaches the 

 machine from the steam-engine, and the whole comes to a stand ; 

 and so it remains, like an inanimate corpse, until recalled to 

 activity by the renewal of its moving power. 



But, say the reasoners who deny that force is anything else 

 than a fiction of the imagination, the revolving shaft of the steam- 

 engine is " matter in motion ; " and when the connection is 

 established between that shaft and the one that drives the 

 machine, the motion is communicated from the former to the 

 latter, and thence distributed to the several parts of the mechan- 

 ism. This account of the operation is just what an observer 

 might give, who had looked on with entire ignorance of every- 

 thmg but what his eyes could see ; the moment he puts his hand 

 upon any part of the machinery, and tries to stop its motion, 

 he takes as direct cognizance, through his feeling of the effort 

 required to resist it, of \hQ force which produces that motion, as he 

 does through his eye of the motion itself 



Now since it is universally admitted that our notion of the 

 external world would be not only incomplete, but erroneous, if 

 our visual perceptions were not supplemented by our tactile, so, 

 as it seems to me, our interpretation of the phenomena of the 

 universe must be very inadequate, if we do not mentally co- 

 ordinate the idea of force with that of motion, and recognize it as 

 the " efficient cause " of those phenomena, — the " material con- 

 ditions" constituting (to use the old scholastic term) only ''their 

 •' formal cause." And I lay the greater stress on this point, because 

 the mechanical philosophy of the present day tends more and 



