250 PHILOSOPHY OF STORMS. 



tion, from about N. E. ; and in the second half, from nearly 

 S. W. But all our inquiries serve to show that the gale is 

 violent at N. E. only on the northern portion of the track 

 of the tempest, and that the usual changes from this direc- 

 tion are not sudden, and to an opposite point of the com- 

 pass; but instead thereof, we observe a gradual veering by 

 the N. to the N. W." 



I accept this test with the corrections which I am sure 

 Mr. Redfield will allow, namely, on Mr. Redfield's theory 

 if the wind sets in N. E., in storms on our coast, it never 

 can change round to N. W., not even gradually, as he ac- 

 knowledges it does. Second, this test can only apply to 

 round storms, and if any shall be found with their N. E. and 

 S. W. diameter much longer than their N. W. and S. E., 

 then if such a storm moves towards the eastern quarter, 

 the wind, on my theory, ought to set in from S. E., and 

 change suddenly round to N. W., as a general rule. 



It being always understood that allowance is to be made 

 for oblique forces produced by various causes, but especially 

 by an annulus or semi-annulus of increased barometric 

 pressure to the N. or N. E. of the storm in its onward mo- 

 tion. Let us then put the theory to the torture. 



Numerous examples were given in the storm of 1821, 

 before investigated, all harmonizing with the test here pro- 

 posed by Mr. Redfield, to which the reader is referred in 

 articles 155, 156, and 157. Nor is the present storm of 

 1837 wanting in remarkable examples. The Ida changed 

 round from N. E. to S. W. in twelve hours, having begun 

 at N. N. E., and continued to blow, all day of the 18th, 

 S. W., exactly towards the Rawlins and the Yolof, during 

 which time the centre of the storm passed near both those 

 ships. The Rawlins, also, which remained nearly station- 

 ary during the storm, as appears by her log, had the wind to 

 set in N. E. by E., and changing round to N., after a calm 

 of one hour, sprung up quick as thought from the south west. 



