54 jAccount of some Experiments 



the beam of daylight, which is illuminated by the 

 yellow light of a candle, should be of a yellowish hue, 

 is not surprising ; but why is the shadow correspond- 

 ing to the light of the candle, and which is illuminated 

 by no other light than the apparently white light of the 

 heavens, blue? I at first thought that it might arise 

 from the blueness of the sky; but finding that the 

 broad daylight, reflected from the roof of a neighbour- 

 ing house covered with the whitest new-fallen snow, 

 produced the same blue colour, and if possible of a still 

 more beautiful tint, I was obliged to abandon that 

 opinion. 



. To ascertain with some degree of precision the real 

 colour of the light emitted by a candle, I placed a 

 lighted wax candle, well trimmed, in the open air, at 

 mid-day, at a time when the ground was deeply cov- 

 ered with new-fallen snow, and the heavens were over- 

 spread with white clouds; when the flame of the 

 candle, far from being white, as it appears to be when 

 viewed by night, was evidently of a very decided _;/^//c'zc 

 colour, not even approaching to whiteness. 



The flame of an Argand's lamp, exposed at the same 

 time in the open air, appeared to be of the same yellow 

 hue. But the most striking manner of showing the 

 yellow hue of the light emitted by lamps and candles 

 is by exposing them in the direct rays of a bright 

 meridian sun. In that situation, the flame of an 



to permit my paper to go forth into the world in its original state. I conceived 

 that it would show, in a very striking manner, if not the advantages which 

 sometimes result from forgetting what we have read, at least the very great 

 importance of preserving the mind totally unbiassed by the speculative opinions 

 of others when we are in search of truth. 



An ardent lover of science will not hesita e to expose himself to personal 

 danger, when he perceives that by so doing he has a chance of promoting useful 

 investigation. 



