:>4 OF CLOUDS. CHAP. 2. 3. 



extensive sheets of this cloud, covering the 

 welkin before its condensation into water, that 

 the Halo appears.* It is this cloud which, un- 

 der some known circumstances of atmospheric 

 change, first in a diffused form obscures the 

 sky, giving the sun, moon, or stars that dim 

 light, and those peculiar refractions, spoken of 

 in another place, and which often eventually 

 becomes nimbiform, and ends in gentle and 

 continued Rain. The sun often sets apparently 

 shrouded in a dense feature of this modification, 

 and this is a sure indication of a wet morning. 

 But let us turn to more elegant varieties of the 

 Wanecloud, which sometimes appear in longish 

 irregular spots, or in bars in close horizontal 

 position.f Features of this kind are frequently 

 of short duration, and move along very slowly 

 in a high atmosphere, and appear subsiding by 

 degrees; while perhaps other beds of it are 

 forming in other places : a feature much like 

 this appears in the intervals of Showers.t There 

 also appears in variable weather, and before 



* See Chapter III. t PL II. Fig. 2. 



J What is called the mackerelback sky often consists of 

 this feature spread over a large portion of the firmament : but 

 a sort of cirrocumulus, in like manner spread aloft, likewise 

 receives this whimsical appellation. 



