378 DIVERSIONS OF A NATURALIST 



Probably no one would have cared very much a 

 couple of hundred years ago if toads were constantly 

 present in the centre of solid stones. Toads were 

 regarded as queer, dangerous things connected with 

 witchcraft, and there was no accounting for their 

 behaviour. The view taken by the well-to-do class 

 would have been in those days (as perhaps it would 

 be less generally to-day) similar to that of the Chicago 

 millionaire when shown, by means of the spectroscopic 

 examination of light, the proof of the existence of the 

 metal sodium in the sun. The professor who took the 

 millionaire round his laboratory wished to interest him 

 in the discoveries of science, and hoped that he might 

 contribute to the funds necessary to pay for the elaborate 

 and delicate instruments by which such discoveries are 

 made. He showed many remarkable experiments to 

 his visitor, and wound up by showing him the two 

 narrow lines of yellow light caused by incandescent 

 sodium. He showed him how exactly their position 

 in the spectrum could be fixed and measured ; how 

 they caused two black lines in the spectrum of light, 

 which was made to traverse a flame in which in- 

 candescent sodium was present. And then he showed 

 him that in the spectrum of the sun's light there were 

 two black lines (besides thousands of others) which 

 exactly coincide with the two sodium lines ; whilst 

 others of the black lines in the solar spectrum coincide 

 with bright lines given out by incandescent hydrogen, 

 iron, magnesium, etc. The millionaire followed it all 

 and understood the completeness of the demonstration. 

 The professor was delighted and hopeful. Then the 

 millionaire said, " Who the hell cares if there is sodium in 

 the sun ? " I was not told by the disappointed professor 

 (it was Professor Michelson, and he related this little 

 episode at a dinner of the Royal Society) what reply he 



