THE AMERICAN STORM OF DECEMBER 20, 1836. 



In accordance with the preceding nnmbers, the lines of equal thermomctric dis- 

 turbance have been drawn upon the five accompanying charts. On each chart is 

 drawn the line of mean temperature, and on most of them are drawn lines of ten, 

 twenty, and thirty degrees below the mean, as well as lines of ten, etc., degrees 

 ahnre the mean. On each of these maps, there appears a large area over which the 



