Stars tn 2)agK0bt 93 



such men as Pierre Balmat and Marie Coutet, told De 

 Saussure that they had seen the stars in broad daylight, 

 but De Saussure himself confessed that he could not 

 detect them. Now Mont Blanc is not quite 16,000 ft. 

 high ; El Misti is about 19,000 ft. high, and the stars 

 from even its soaring summit are invisible with the 

 naked eye in the day-time. 



In my own experience, I have seen the planets 

 Jupiter and Venus without optical aid just after sun- 

 rise, an hour or two after noon and half an hour or 

 more before sunset, but not a star of any magnitude 

 whatever. It is true that I have not yet descended 

 to the bottom of a deep well, nor have I yet peered up 

 the shaft of a tall chimney, nor, indeed, up through 

 the mouth of a pit, but if I did do any of these things 

 I should not expect to see the stars in broad daylight. 



n 



One writer on astronomical subjects who has at- 

 tained a considerable degree of popularity, has stated, 

 I know, that for the stars to be seen in daylight it is 

 necessary only to look up a vertical shaft. On the 

 other hand, this is held by an astronomer of some 

 authority to be " not proven." I myself do not forget 

 that when Humboldt was engaged in practical mining 

 operations and was spending a great portion of the 

 day underground, during many years, he on no occa- 

 sion was able to observe a star, though he could see the 

 sky through the deep shafts. Neither, let me add, did 

 he ever meet with any individual in the Mexican, 

 Peruvian, or Siberian mines who had even heard of 

 stars having been seen by daylight. This matter had 



