Vertical Height of the Storm-Wind. 185 
storm, but, by careful observations, may be:sufficiently noticed to 
determine the general uniformity of its specific course, and, ap- 
proximately, its general elevation. 
The more usual course of this extended cloud stratum, in the 
United States, is from some point in the horizon between 8. S. 
W. and W. 8. W. Its course and velocity do not appear influ- 
enced, in any perceptible degree, by the activity or direction of 
the storm-wind which prevails beneath it. On the posterior or 
dry side of the gale, it often disappears, before the arrival of the 
newly condensed cumuli and cumulo-stratus which not unfre- 
quently float in the colder winds, on this side of the gale. 
It ap , therefore, that the proper storm-wind revolves en- 
tirely below the great stratus cloud which covers so large a por- 
tion of the storm; and we may infer, also, that the production of 
the accompanying rain and the depressing effect of the storm’s 
rotation on the barometer, are chiefly confined within the same 
vertical limit. In regard to rain, this result is in accordance with 
observations on the quantity acbadh falls at different elevations 
above the earth’s surface ; and in the case of the barometer, a like 
accordance is shown in the diminished range of the mercury in 
storms which is found in ascending from the ocean level. 
» The general height of the great stratus cloud which covers a 
Storm, in those parts of the United States which are near the At- 
lantic, cannot differ greatly from one mile ; and perhaps is oftener 
below than above this elevation. This estimate, which is found- 
ed on much observation and comparison, appears to comprise, at 
the least, the limit or thickness of the proper storm-wind, which 
constitutes the revolving gale.* 
It is not supposed, however, that this disk-like stratum of revol- 
ving wind is of equal height or thickness throughout its extent, 
* See this Journal, vol. xxxi, p- 127—128. Ifa disk be cut from the thin paper 
of Chart IV, of a size which will ve am one thousand miles in diameter, it will 
be found to mee a thickness whic nts more than a vertical mile, by the 
scale of the chart. A disk of the same size, but on a scale representing a vith of 
but 400 miles diameter, if cut from the paper of this Journal, will also represent more 
than a mile of vertical thickness, in the storm. These and other analogous con- 
supposed paths of vertical induction and geographical tore a in the winds, 
_ 0M an accurate and uniform linear and vertical scale, for the purpose of — 
& more precise standard for estimating the supposed vertical action or influence 
