154 FRACMI:NTS OF SCIENCE. 



imagination, retires in bewilderment from the contempla 

 tion of the problem. We are struck dumb by an astonish 

 ment which no microscope can relieve, doubting not only 

 the power of our instrument, but even whether we ourselves 

 possess the intellectual elements which will ever enable us 

 to grapple with the ultimate structural energies of Nature. 

 But the speculative faculty, of which imagination forms 

 so large a part, will nevertheless wander into regions where 

 the hope of certainty would seem to be entirely shut out. 

 A\V think that though the detailed analysis may be, and 

 may forever remain, beyond us, general notions may be at 

 tainable. At all events, it is plain that beyond the present 

 outposts of microscopic inquiry lies an immense field for 

 the exercise of the speculative power. It is only, however, 

 iho privileged spirits who know how to use their liberty 

 without abusing it, who are able to surround imagination 

 by the firm frontiers of reason, that are likely to work with 

 any profit here. But freedom to them is of such paramount 

 importance that, for the sake of securing it, a good deal of 

 wild ness on the part of weaker brethren may be overlooked. 

 In more senses than one Mr. Darwin has drawn heavily 

 upon the scientific tolerance of his age. He has drawn 

 heavily upon time in his development of species, and he has 

 drawn adventurously upon matter in his theory of pangen- 

 &amp;lt; sis. According to this theory, a germ already microscopic 

 is a world of minor germs. Not only is the organism as a 

 wlmle wrapped up in the germ, but every organ of the or 

 ganism has there its special seed. This, I say, is an adven 

 turous draft on the power of matter to divide itself and 

 distribute its forces. But, unless we arc perfectly sure thai 

 he is overstepping the bounds of reason, that he is unwit 

 tingly sinning against observed fact or demonstrated law 

 for a mind like that of Darwin can never pin wittingly 

 against either fact or law we ought, I think, to be cautious 

 in limiting his intellectual horizon. If there be the least 



