450 The Rev. H. Lloyd on the Meteorology of Ireland. 



of cyclonic movement are passed over, in which the centre of the vortex was 

 remote. The observations themselves are given in detail in Table xxxiii., at 

 the end of this Paper.* The following are their principal results : — 



1850. Oct. 6, 7. — Cyclone and storm, moving from S.W. to N. E., with a 

 velocity of about 290 geographical milesptT diem. (Plate vm. Figs. 1, 2, 3.) 



Oct. 6, 9 A. M. — Centre of the vortex on the south-western coast of Ireland, 

 west of Kilrush. Least pressiu^e at Cahirciveen. Mean velocity of the wind 

 = 25 feet per second ; greatest do. (on the west coast) = 45 feet. The atmo- 

 sphere at the northern stations unaffected by the vortex at this epoch. 



Oct. 6, 9 p. M. — Centre of the vortex over the north of Ireland, a few miles 

 north of Killybegs. Absolute barometric minimum (= 28"836) at Killybegs; 

 increase of pressure in 100 miles = 0"30 inch. Mean velocity of wind = 35 feet 

 per second ; greatest do. (Markree) = 70. Southern stations unaffected by the 

 vortex. 



Oct. 7, 9 A. M. — Centre on south-western coast of Scotland. Least pressure 

 at Donaghadee. Mean velocity of wind = 45 feet per second ; greatest do. 

 (north coast) = 60 feet. Hail fell at Markree; wind amounting to a gale in 

 the north, in the evening of the same day. 



The diameter of the vortex may be estimated with tolerable precision in 

 this case, by measuring from the centre to the limits of the region affected by 

 the movement ; it was about 280 geographical miles. 



Oct. 22, 23. — An interesting and instructive case of conflicting currents 

 generating a rotatory movement. The velocity of the wind was uniform 

 throughout the island, and was from 30 to 35 feet per second. (Plate viii. 

 Figs. 4, 5, 6.) 



Oct. 22, 9 p. M. — Wind from N. AV. in the north of Ireland, and from S.W. 

 in the south-east. The central point of junction of these currents was over 

 the channel, to the north-east of Dublin. Least pressure at Donaghadee. 



• It seems certain that a careful study of the simultaneous atmospheric phenomena, even in a 

 limited district, will throw more light upon the " law of storms," than any other mode of inquiry ; 

 and for this reason, as well as for the authentication of my own inferences, I have thought it right 

 to give these observations in extenso. It is probable that an attentive examination of them may elicit 

 many conclusions which have escaped my notice. 



