THE CLIMATOLOGY OF THE UNITED STATES. 43 



under certain circumstances without the attendant dis- 

 turbances. 



Another fact in connection with the w Yellow Day" is 

 that the same yellow light was observed within a day or 

 two after, in Virginia and then in Iowa. In the latter 

 state the light had a flashing appearance like the northern 

 lights in activity. It certainly seems quite unreasonable 

 to suppose that smoke came down to New England, then 

 passed to Virginia and then over to Iowa. The only 

 satisfactory way to account for it is, as above stated, on 

 the supposition that it was caused not by the mere inter- 

 ference of gross matter held in suspension in the air, but 

 by the same forces and conditions which are concerned in 

 the production of many other singular terrestrial and 

 aerialphenomena, and which may have much to do with the 

 aurora borealis and the red afterglows at sunset which 

 have attracted so much attention within the last two or 

 three years. These brilliant results began in the fall of 

 1883, appearing in India in September, and being very 

 marked in October, November and December, not only 

 in Asia, but in Europe and America. The display began 

 when the ordinary ruddy glow of sunset had faded ; then 

 a deep red light illumined the western sky, extending at 

 times even to the zenith. A writer, describing the ap- 

 pearance in New England, says : "The display was al- 

 most startling and there was something almost bewilder- 

 ingly grand in the evidences of the red glow. It was at 

 almost six o'clock that the most peculiar phase of the 

 phenomenon was witnessed, when in the starlit sky the 

 peculiar ruddy glow came and went. The coldly bril- 

 liant stars seemed blue and green by contrast with red 

 and their brilliancy was fantastically magnified." Astron- 

 omers and meteorologists here and abroad advanced dif- 

 ferent theories and each seemed plausible. Prof. Piazzi 



