Fig. i. — Cirrus Clouds 



Light, feathery clouds that float at an elevation of 4 or 5 miles above the 

 earth's surface. When in the form of plumes with frayed and torn edges in- 

 creasing cloudiness and rain or snow are indicated. 



Photos by Henry 



Fig. 2. — Cirrus, Merging into Cirro-Stratus Clouds 



A transitional form often seen when rain or snow is approaching. The cloud layer 

 gradually thickens until the sky is obscured 



