180 ON TWO STORMS EXPERIENCED THROUGHOUT THE UNITED STATES, 
No. 2. 
The accompanying charts will show that neither of these diagrams faithfully represents 
the storms here investigated, and it is doubtful whether either of them ever accurately re- 
presents the motion of the wind over any large portion of the earth’s surface. ‘The storm 
of December 15, 1839, has been quoted as a strong case of the revolving kind, and if we 
take only a semicircle of two hundred miles radius on the north-west side of the centre, 
the correspondence is very good, (see Mr. Redfield’s diagram, Philosophical ‘Transactions 
Volume viii., page 81,) though, even here, most of the arrows are inclined to the circum- 
ferences drawn, and, as Mr. Redfield has remarked, the direction is generally inward 
towards the centre of the storm. But if we take the other half of the semicircle, which 
Mr. Redfield has omitted, the circles are not completed. ‘There have been several cases, 
of limited extent, in which the winds might be represented by figure No. 1.; but I have 
seen no account of a storm, of a hundred or more miles in diameter, in which the winds 
could be faithfully represented by either of the above diagrams. A combination of the 
two is, however, frequently seen. No. 8 is intended to represent the motions of the 
‘ eh ~m 
wind February 16, 1842, at sunset, near the centre of the storm. Substantially the same 
diagram is applicable for the morning <i the seventeenth, so far as appears from the 
observation, and tolerably well for sue morning of the sixteenth, although there is here 
more irregularity, the storm being of larger dimensions and less violent. 'The lower 
half of this diagram represents, very faithfully, the observations for the morning of 
December 21, 1836; and it may be inferred that if observations could be procured from 
more northern stations, they would show the other half of the diagram. The same figure 
