CLOUDS. 143 



considered indicative of fine weather. Among this variety of 

 clouds are included those fogs and creeping mists that in summer 

 evenings fill the valleys, remain during the night, and disappear 

 in the morning. The formation of the cumulus is best viewed 

 in fine settled weather, about sunrise or a little after. Small 

 specks of cloud will be seen in the atmosphere, which seem to be 

 the result of the gatherings of the stratus or evening mists, which 

 rising in the morning form into small clouds whilst the rest of the 

 sky becomes clearer. About sunrise two or more of these unite 

 and form a stacken-cloud. In the evening it again subsides giv- 

 ing place to the stratus or fall cloud. In our engraving the cu- 

 mulus is seen above and the stratus nearer the horizon. Some 

 varieties of the cumulus are supposed to be closely connected 

 with electrical phenomena. The hemispherical form is more 

 perfect in fine than in changeable weather. 



The Cirro-stratus is often called a mackerel sky, and is seen 

 in fine summer evenings, it is generallly called the wave-cloud 

 on account of its frequent alterations of figure. It is formed ut 

 a great height and presents many varieties and is sometimes seen 

 as a thin extensive sheet covering the heavens, and it is this form 

 of the cloud in which the halos appear, which are thought to in- 

 dicate rain, and when the sun sets apparently shrouded in a dense 

 stratum of this cloud it is a .mre indication of a wet morning. A 



