182 Phenomena of the Cuba Huricane. 
Mr. Luoyp. It is proper to add, also, that Port Louis is situated 
near an abrupt ridge of mountains which might have greatly dis- 
turbed the regular course of the wind at that place. 
With a higher rate of progression the center of gyration might 
move on a line or course more like the following : 
Fig. 2. 
LMI 
But with a very rapid progression in the body of the storm, 
like the case before us, the revolving center or point of gyration 
might describe a line more nearly like one of the two following 
figures. 
Fig. 3.) :° 
Fig. 4. 
Such oscillations of the axis of a storm, however, cannot easily 
be detected, for want of sufficient and exact observations in the 
axis path, in those regions where the winds have free action. 
They may be best noticed in a storm of slow progress, like that of 
Mauritius, above mentioned, but may also be often evinced in 
other observations. In the case before us, we find cause to infer 
that some deviations existed in the axial course, without being 
able to determine these with precision. 
Crecurr Samine 1x Storms.—In the rapid progression of the 
Cuba hurricane, no great portion of a circuit of revolution would 
be described by any vessel, in sailing before the wind. Nor is 
the ordinary progress of the Atlantic gales sufficiently slow to in- 
duce often such a result, under the courses ordinarily steered in 
these gales. But I have formerly shown a case on the American 
coast, furnished me by Capt. T’. H. Sumner, where a ship, in scud- 
ding before the gale, performed nearly half the circuit of the hor- 
izon, before the gale abated.* 
In the slow progression found in storms of the eastern seas, 4S 
noticed, not only a complete circuit of revolution, but more 
* Ship Cabot. Son temennkal Fmebindaniante tans A, vol, xxiii, p. 3705 
with a diagram. 
