The width of that portion of the ack ee was 2 Salih 
ited either the violence of a hurricane or that of a severe or de- 
structive gale may be estimated to exceed five hundred miles.* 
D1taMeTer OF THE Storm oN ITs Center Patu.—The diameter 
of the storm-wind from front to rear might be directly determin- 
ed by the distance from a point in front to another in rear at which 
it severally began or ended at the same time; provided that we 
could obtain good hourly observations which should so coincide. 
An available substitute for this method is found in plotting the 
observations for a given hour, on successive days, as on Chart IV, 
and the other charts which follow. Thus the distance between 
the two several positions assigned to the axis of the storm at noon 
- on the 5th and 6th days of October, respectively, is 784 miles. 
Now the Demarara, (45b,) in front of the gale on the 5th, was 
brought to reefed topsails as early as 8 a. m.; while at noon on 
the 6th, after an advance or drift of 88 miles in the Gulf Stream, 
this vessel remained hove to, and did not set reefed topsails till 1 
P.M. ; nor let out reefs and make full sail till 6 vp. m., a period of 
34 hours. This authorizes an estimate of 1084 miles for this 
diameter of the storm as a reefed topsail gale. 
The distance between the two axis positions on Chart TV for 
noon of the 6th and 7th, respectively, is 950 miles, and the ob- 
servations of the winds and minimum of the barometer on board 
the Pique frigate appear to show that the storm figure for noon of — 
7th should have been placed thirty miles further in advance, mak- — 
ing the distance between the two axial points equal to 980 miles. 
Now, even at Bermuda the strength of the gale was marked 6 at 
two hours before noon of 6th; and, more in front, the gale was 
_ strong with the Wakulla (148) at noon, and continued to blow 
a gale till noon of the 7th. These facts indicate a diameter of 
more than a thousand miles. These — inelude neither 
the incipient nor the closing moderate and light winds whic 
were conformable with the body of the oe 
Another good estimate of the diameter in this direction is ob- 
tained by multiplying the rate of progress by the whole duration 
of the storm wind, at the several points where the observations 
have been most complete. If we apply this to the éntire obser- 
vations at Key West, (38,) about 48 hours, with an average rate 
* Recitals 11, 0, 66, 118,, ree 156, and — 
