Curves of Barometric Progression. 15 
poke, nearly the same: as also at Charleston, S. C., nearer to 
the path of the storm; and scarcely falling below 30 inches at 
New York and Nantucket, as the storm passed, But at Camden, 
S. C., 140 miles N. N. W. of Charleston and 280 miles W. S. W. 
of Hatteras, the successive maxima on the 6th and 8th were only 
30°04, and 30 in nches; showing this place to have been beyond 
the crest of the external barometric wave. When storm-tracks 
recurvate on the interior meridians of the United States, the 
minimum depression of the barometer frequently moves nearly 
parallel to the direction from Camden either to Hatteras or to 
Chesapeak Bay.* 
The annexed diagram shows the barometric curve at Washing- 
ton, Fort Monroe, steamer Georgia, and Bermuda, while the 
storm was passing between the latter and Washington. These 
two places are distant from each other about 840 miles; which 
perhaps may be considered as an approximate measure of the 
barometric diameter of the storm on the 7th of September. The 
barometric curve of the Georgia, if increased so as to reach the 
minimum of the Swan, may represent a section through the cen- 
ter of the cyclone, in the direction of the storm’s progression. 
Storm-Curves of barometric progression. 
A. M, Sepremser 7th A Paes |] Serr. 8th, A. M. 
3 6 9 12 3 6 9 12 3 6 9 
ee Se % OMe Ce & pha * Ae oe ek a a 

30 in. 





~ 
= 
om ey 
4 ” 7 
Ca - 
@ Ca - 
ig e 4 29in. 
oi F 
x 
= af 4 
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28 in. 4 2 J xin. 
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Pe sites cnx cena ee eee 
Ll a at Washington: 2, at Fort Monroe: 3, Steamer Georgia: 4, Brig Swan: 
5. Ship Eagle, crossing in front of storm: 6. Bermuda. 
i officers of the Smithsonian Institution, and 
to Gen. 2 nda yy. mea ran at Ny png for aah esr from 
Various of the United S o Lieut. Maury, 5 upt. of the Naval Obser- 
nea Rr al abstracts of the books of of Ship Eagle, and steamer Northern Light, 
Surgeons Wi and Harrison of the Navy, and many ship-masters, and others 
have kindly aided my inquiries. 
