322 Dove on the Law of Storms. 



Both suppositions agree in leading us to expect a rotation with 

 the sun on the southeastern side of the storm, and against the 

 sun on the northwestern side ; and in the middle a calm, dividing 

 winds blowing in opposite directions ; but they disagree in ma- 

 king a difference of 90° in the two opposite positions of the 

 wind vane at the commencement and at the termination of the 

 rotation. 



The observations in the memoir referred to are decidedly in 

 favor of the second view, and adverse to the first ; for the rota- 

 tion of the vane never begins with N. N. E., N., or N. N. W., and 

 ceases with W. S. W., W., or W. N. W., but always begins with 

 E. S. E. and S. E., and ceases with S. VV. and W. It was so in 

 Germany, Italy, Denmark and Russia. In England the wind 

 before the minimum was east, not north ; in France it was prin- 

 cipally S. W., and in Iceland it was first N. E. and afterwards N., 

 just as the rotatory movement would require at a point so distant 

 from the centre. 



[In a map accompanying the original memoir, M. Dove has 

 marked the successive circles of the rotatory storm as it advanced 

 from the beginning to the end of the observations, in order to 

 facilitate the comparison of the observations with the theoretical 

 assumption. Where the advancing circles are stopped by the 

 Spanish mountains and the Maritime Alps, those points are as- 

 sumed as centres of new circles or whirlwinds.] 



The observations give — 



1. On the Northwest side of the Storm. 

 Naes in Iceland, N. E., N. 



2. Nearly in the middle of the Storm. 



Helston, E., min., W. Cambridge, S.E., min., W. 



London, S. E., min., N. W. New Malton, southerly storm. 



Owen's Row at Islington, S. E. 3 

 min., N.W. 



3. On the Southeast side of the Storm. 

 Boulogne-sur-Mer, S. S. E., S. } Vivarias, S. E., min., S. E. 



E. N. E., min., W. N. W. Strasburg, S. E., E., S., min. 



Paris, S., min., W. S. W. Haarlem, S. E., E. S. E., S.S.E., 

 Joyeuse, southerly storm, min. min., S. S. W., S. W. 



Nismes, S., min., S. W., N. W. Schwelm, S., min., S. W. 



