THE ELECTRIC ELEMENT. 85 



living world. Though forced to use the term im- 

 ponderable for this element, yet does its function need- 

 fully imply the material nature of the medium, as well as 

 its diffusion throughout every part of the solar system, 

 and even through those other systems of worlds which 

 send their light to us from the. depths of space. It is a 

 cosmical element in the largest sense of the word ; not 

 merely diffused through the universe around us, but 

 interpenetrating, as optical and other phenomena attest, 

 even the densest bodies of our material world. 



Vast and complex though the recognised function 

 of ether be, need we or can we suppose it the sole 

 one which this element fulfils in nature ? Admitting 

 in the outset its materiality, may it not, or must it not, 

 when coming into contact and interpenetration with 

 the atmosphere and still grosser and more palpable 

 forms of matter, assume other conditions and properties 

 than when diffused equably and continuously through 

 outer spacebe condensed, accumulated, evolved, con- 

 ducted in currents, and otherwise modified by the kind 

 of matter it pervades, and by the changes matter itself 

 undergoes from other forces acting upon it ? 



Say that these questions are vague and lead to 

 presumptions only. But presumptions may fairly be 

 made an integral part of science in cases where cer- 

 tainty is unattainable or has not yet been attained. 

 They are steps to rest upon, if not to aid in rising 

 higher. In the case before us the general presumption 

 is one that almost compels assent. An exquisitely 

 subtle agent, such as we must presume ether to be, 

 cannot be supposed to impinge upon, interpenetrate, 



