58 HERSCHEL AND HIS WORK 



proof that the matter of which it is composed is similar 

 to that of our earth, and also proves the existence of 

 a lunar atmosphere, which some philosophers have 

 doubted. The science of astronomy is therefore in- 

 finitely indebted to the zeal of Mr. Herschel. 



" This phenomenon was also seen by Count Bruhl, 

 Mr. Cavendish, Mr. Aubert, etc. Yours, etc., Z. Z." l 



Lalande, of the Royal College of France, told a 

 somewhat more wonderful story to the scientific world 

 in a paper which he wrote for the Academy of Dijon. 

 " Herschel," he says, " has seen in the moon two peaks 

 or mountains formed almost before his eyes ; there are 

 in their neighbourhood certain currents resembling 

 those torrents of lava that flow from a volcano at the 

 time of its greatest eruption. This observation was 

 confirmed by an actual eruption very visible in his 

 telescope of 9 feet : it is a fire or light like that of a 

 star of the fourth magnitude seen by the naked eye, 

 and it appeared on the obscure part of the moon. This 

 may help to explain the observation of Ulloa, who, in 

 the total eclipse of 1783, saw in the middle of the 

 moon a luminous point, which he conjectured to be a 

 perforation." Alas for the astronomers who probably 

 saw what they devoutly wished to see a volcano in 

 action on the moon ! It was all moonshine, apparently 

 a reflection of light from our earth, when sixteen times 

 the amount of light showered on us at full moon is 

 then thrown by us on her ! But a hole through the 

 middle of the moon, perhaps twenty miles round ! 

 There is no air that we know of on the half of the 

 moon that we see, and there is no water. There are 

 1 Scots Magazine, vol. xlix. 318, quoted from Gentleman's Magazine. 



