134 HERSCHEL AND HIS WORK 



30 ... even 1 to 300 is sufficiently striking to 

 draw our attention." These were the words of a 

 wise observer, uttered long before geologists had 

 begun to use similar language in their own researches. 

 The conclusion which Herschel drew from these 

 alterations, real or imagined, in the light of the stars 

 was that they will "much lessen the confidence we 

 have hitherto placed upon the permanency of the equal 

 emission of light of our sun. Many phenomena in 

 natural history seem to point out some past changes 

 in our climates. Perhaps the easiest way of account- 

 ing for them may be to surmise that our sun has been 

 formerly sometimes more and sometimes less bright than 

 it is at present. At all events it will be highly pre- 

 sumptuous to lay any great stress upon the stability of 

 the present order of things ; and many hitherto unac- 

 countable varieties that happen in, our seasons, such as a 

 general severity or mildness of uncommon winters or 

 burning summers, may possibly meet with an easy solu- 

 tion in the real inequality of the sun's rays." If our 

 sun be a variable star diffusing heat in greater or less 

 degrees at different times, or if it be a star growing 

 old and burning out, the credit of the idea as well 

 as of " lost" stars in the ocean of infinitude may justly 

 be claimed, in our day at least, for this poetic and 

 musical observer of the heavens. To shed a ray of 

 light on this question of sunshine Herschel sought, 

 but sought in vain, for temperatures in ages that were 

 past. He could get none. He was not aware of 

 the thermometers made by the school of Galileo 



which had been made" was the British catalogue published by 

 Flamsteed in 1712, and afterwards in better condition in 1725. It 

 contains about 3000 stars. See Lalande, i. 284. 



