GO ON MATTER, FORCE, AND MOTION IN SPACE. 



with terrestrial matter. Look at all we have to con- 

 ceive when these complex ethereal pulses reach the 

 region of our atmosphere. Three gases, besides aque- 

 ous vapour in ever-varying degree of condensation and 

 change, become blended with them in the self-same 

 space, under what physical relations no philosophy can 

 tell. Nearer to the earth other matters, organic or 

 mineral, are variously diffused through the atmosphere ; 

 and the atmospheric vibrations ministering to sound 

 become commingled with the undulations conveying 

 light to heat ; each system of waves, under their 

 several velocities, amplitudes and refrangibilities, mov- 

 ing in the same portion of space not indeed without 

 conflict, as shown in the various modifications of the 

 calorific and actinic rays, as well as of the lines of the 

 visible spectrum but still under laws, seen or unseen, 

 which limit disturbance and control the whole. Con- 

 ception labours in vain to follow these infinitesimal 

 functions of matter and force. And the difficulty is en- 

 hanced by the conclusion pressed cogently upon us that 

 the great agent under our review, the ether of space, 

 exists in and permeates the most solid bodies of which 

 we have knowledge a medium or agent in those in- 

 testine molecular changes which, in one condition of 

 action or another, form the subject and foundation of 

 all physical science. Our knowledge of the infinitesi- 

 mal divisibility of matter helps us to the conception of 

 ether pervading it no farther than by the analogy of 

 another great natural fact, closely related, equally 

 inconceivable, yet proved to be true. This topic, how- 

 ever, does not now come before us. 



