Arr. XXIX.—On Three. several Honricasies of the American 
_ Seas and their relations to the Northers, so called, of the Gulf 
of Mexico and the Bay of Honduras, with Charts tllustrating 
_ the same; by W. C. Rupriexp. 
thee . (Continued from Vol. II, p. 187.) 
Phenomena of the Cuba Hurricane and Cotemporary Storms, 
_ Errecr or tHe Gaue’s Roration oN THe Baromerer.—The 
extraordinary fall of the mercury in the barometer which takes 
place in gales or tempests, has. attracted attention since the earli- 
__- @st_use of this instrument by meteorologists.. But lam not aware 
i that the principal cause of this depression had ever been pointed 
ee Gath previously to my first publication in this Journal, in April, 
1831; when I took the occasion to notice this result as being ob- 
viously due to the centrifugal force of the revolving motion found 
in the body of the storm.* 
' Since that period, inquiries have been continued by meteorol- 
3 ogists in regard to the periodical and other fluctuations of the ba- 
iad Tometer, and the relations of these fluctuations to temperature and 
Aqueous vapor.+ But these incidental causes of variation in the 
atmospheric pressure prove to be of minor influence, and we are 
left to the sufficient and only satisfactory solution of this marked 
Phenomenon which is found in the centrifugal force of rotation. 
_ In the Cuba Hurricane, the fall of the barometer may now be 
Viewed in its obvious relations to the known rotation of the gale. 
Tn the previous Tables, I, I, and III, the reader may have noti- 
ced the depressing effects of the centrifugal force at different dis- 
tances from the storm’s axis and in the various stages of its ac- 
uivity and progression. These tables enable us to determine, ap- 
Proximately, the mean of the barometric curve, through the cen- 
‘al portion of the storm, transversely to its path, as shown by 
the lowest observations obtained during its progress, which may 
be grouped as follows: 
* 
¢ 
oo 
~~. 
‘This Journal, xx, 45-46. hi sae ’s surf 
TEE Spbarent that hygrometrical observations made at the earth s surface can- 
: © relative condition of the higher strata of ait, which move, as cur- 
t i De he > + } 
? .—) J ys 
can observations at mountain stations re- 
ok: 
a 
