REMARKS UPON METEOROLOGY. 3 



would move to the right or the left; hut there were several 

 circumstances, which rendered it probable, that the wind 

 would go towards S; the arc was strongly precipitating 

 and there was a small contiguous solar halo, by which is Hal °* 

 meant, a halo that is close to the sun, and not one that 

 forms a large circle at some distance from it. This combi- 

 nation of pheuornena seemed to show, that there was a cur- 

 rent of air passing above the wind in a southerly direction, 

 and that this upper current was loaded with aqueous parti- 

 cles in a different state from those in the wind. When I 

 first observed these appearances, I fully expected rain from 

 the S ; but when, after some time, I perceived, that, al- 

 though the rapidity of the upper current increased, yet the 

 lower one decreased and tended to a different direction, I 

 concluded, that the commotion, which at that time affected 

 the upper regions of the atmosphere, would not be felt in 

 this district. Accordingly, only a few drops of rain fell, 

 and for the next 36 hours there was nothing which could be 

 called a shower. This is one of those cases in which com- Comparative 

 parative observations made in different countries would be 

 extremely interesting; we might, by their means, trace the 

 exact limits of a storm, and probably be enabled to ascer- 

 tain the causes which immediately produced it. 



The 5th was what I call a revolving day, i, e. where the A revolving 

 wind gradually moves rouud through the different points of day# 

 the compass; a change which must be distinguished from 

 that where it ceases in one quarter, and then springs up in 

 a different one. The revolutions are either direct or reverse, 

 i.e. in the same direction with the course of the sun, or 

 contrary to it. A reverse revolution, such as took place on Indications 

 this day, is a very general sign of rain, whereas a direct re- ^ rom il * 

 volution is what often takes place in the most settled state 

 of the atmosphere; a rainy night succeeded. During this 

 time there were many indications of ;he atmospherical elec- Atmospherical 

 tricity being in what is usually called a negative state, which eleclnclt y ne * 

 genen»Uy takes place when the wind is E with a low and & 

 falling barometer, in opposition to the more usual kinds of 

 K winds, which are accompanied by a high barometer, aud 

 a strong positive electricity. In cold weather this combina- 

 tion of circumstances is generally attended or succeeded by 

 B 2 the 



