LIGHT THE ETHER IN ITSELF 49 



But where can the leaden dulness be found, to which 

 lines of light are lines of light and nothing more, suggest- 

 ing nothing, revealing nothing, inspiring no deep ponder- 

 ings, compelling no questions, rendering no answers ? To 

 the lips of every one there must surely spring the question, 

 Does such an entity exist by chance ? And is not the 

 answer easy 1 Is it not a mighty triumph of mind ? Does 

 not every line, do not all the lines, carry in them irresist- 

 ible evidence that the ether so ordered is the work of 

 understanding ; that so vast a sea, acting at every point 

 with a perfection which baffles the imagination to realise, 

 has its form and constitution as the fruit of the operation 

 of an intelligence glorious as the glory of those fruits ? 



(2) TJie velocity of light. The velocity with which 

 light travels is nearly a million times greater than in the 

 case of sound. It descends from the sun to the earth in 

 about eight minutes and a half. In one minute it makes 

 11,160,000 miles; in a second 186,000. In a second it 

 would circle round the earth more than seven times. 

 Observations have been carefully taken, and in a vacuum 

 and in air no difference can be detected in the velocity of 

 light of any colour. There is, however, a difference in 

 their velocity, passing through water and other trans- 

 parent substances. 



The velocity with which light travels shows the extra- 

 ordinary sensibility and perfection of the ether. In the 

 journey of a single line of light from the sun to the 

 earth, how much of it is moved in a second, how much in 

 a minute, how much in its whole course! And every 

 part at every point is distinguished by the same readiness 

 to be moved and to move. Every part is distinguished 

 by an elasticity many hundreds of times greater than is 

 found in steel. Every point is characterised by exactly 

 the same measure of elasticity. Nowhere is there hin- 

 4 



