dl 
being of course different at the different epochs. We thus 
find that the centre of the vortex had a progressive motion 
from W.S.W. to E.N.E. ; and that it reached the western 
shores of Ireland about 3 a.m. of the 19th, and quitted the 
| north-eastern about 3 p.m. of the same day. The position of 
these circles at 9 a. . of the 19th, together with the direc- 
tion of the wind at the several stations, is shown in the annexed 
eon ek 
; diagram. The centre of the vortex was then over the north 
a the island, in lat. 54° 20’, long. 7° 30’, very nearly. 
