SCIENTIFIC USE OF THE IMAGINATION 135 



to their powers; so that when these poles and powers 

 have free action, proper stimulus, and a suitable environ- 

 ment, they determine, first the germ, and afterward the 

 complete organism. This first marshalling of the atoms, 

 on which all subsequent action depends, baffles a keener 

 power than that of the microscope. When duly pondered, 

 the complexity of the problem raises the doubt, not of the 

 power of our instrument, for that is wt7, but whether we 

 ourselves possess the intellectual elements which will ever 

 enable us to grapple with the ultimate structural ener- 

 gies of nature. 1 



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 

 pangenesis. According to this theory, a germ, already 

 microscopic, is a world of minor germs. Not only is the 

 organism as a whole wrapped up in the germ, but every 

 organ of the organism has there its special seed. This, 

 I say, is an adventurous draft on the power of matter to 

 divide itself and distribute its forces. But, unless we are 

 perfectly sure that he is overstepping the bounds of rea- 

 son, that he is unwittingly sinning against observed fact 

 or demonstrated law for a mind like that of Darwin can 

 never sin wittingly against either fact or law we ought, 



"In using the expression 'one sort of living substance* I must guard 

 against being supposed to mean that any kind of living protoplasm is homo- 

 geneous. Hyaline though it may appear, we are not at present able to assign 

 any limit to its complexity of structure. " Burdon Sanderson, in the "British 

 Medical Journal," January 16, 1875. 



"We have here scientific insight, and its correlative caution. In fact Dr. 

 Sanderson's important researches are a continued illustration of the position laid 

 down above. 



