90 HEIGHT OF CLOUDS. CHAP. 2. lj. 



throw their painted canopy over the declining 

 car of Phoebus, and mark the place where he 

 has sunk beneath the Ocean, till they fade away 

 by degrees, and are lost in the uniform gloom 

 of Night. 



SECTION XVII. 



Of the Height of Clouds. 



THE mean or average degree of elevation of 

 the different modifications is different. Ac- 

 cording to M. Howard, the cirrus is the highest; 

 the cirrocumulus next; and the cirrostratus, 

 cumulus, and stratus, v successively lower than 

 each other. The cumulostratus, which is a 

 compound cloud, is of vast vertical dimensions : 

 when it forms on a cumulus, the top of it 

 appears to rise higher, and the base generally 

 lower, than that of the cumulus. The nimbus, 

 which is the resolution of clouds into Rain, 

 may be considered as having its base on the 

 earth, and its summit at the end of the fibres 

 of its cirrose crown. 



The modifications have different degrees of 

 elevation at different times ; and sometimes the 



