A CONTINUOUS RECORD OF ATMOSPHERIC NUCLEATION. 



207 



trast between the negligible dry snow effect on January 2 and the wet snow 

 minimum on January 9 is to be noted. The maximum reaches its height (the 

 diffractions actually surpassing the large green-blue-purple corona) during the 

 cold blizzard and snow drift of January 3. As the coronal method breaks down 

 for nucleations exceeding the case for the g-b-p corona, the higher nucleations 

 are merely suggested in value on the charts. There is a fog effect on January 

 7. Moreover, the maximum is well sustained while the winds shift from north- 

 erly to southerly on January 6. 



o 



CHARTS 33, 34. 



After the rains on January 13 and 16 a second march of nucleation into 

 extremely high maxima (January 1 8-2 1 ) coincides with the sweep of very cold 

 weather, ultimately to be broken by the wet snow on January 2 1 . During the 

 remainder of the month there are some suggestive data on the nucleation ac- 

 companying a strong fog, though but few of the active nuclei are probably 

 entrapped in the latter. Cold snow effects on January 26 and 29 may be noticed. 



1 8. February (charts 35, 36, 37) begins with a sweep of cold weather and 

 high nucleation, terminating in the thaw and fog of the 7th. The next cycle 

 extends to the snow on the i4th, a low minimum, remarkable as being below 

 freezing. The temperature effect from February 1 2-14 is obscure. High nuclea- 

 tion again prevails until the rain and thaw on February 22. The large number 

 of observations entered are due to a number of subsidiary experiments made 

 during this interval. There is cold snow on February 15 and 19. Even the 

 dense snow-storm on February 24 only partially removes the nucleation, as this 

 falls off gradually into the minimum following the rain of February 29. 



