41. Cirrus, Fine, not Increasing; Scarce, Hi. 



This form is distinguished chiefly by its scarceness and also by the 

 fact that it does not increase in amount or tend to fuse into a cloud 

 sheet or pass into cirrostratus. The cirrus plume in this picture was 

 the only one in the sky; it did not increase in amount during the 

 afternoon and disappeared entirely at sundown. (Photo at Washing- 

 ton, D. C, by G. Slocum.) 



42. Cirrus, Fine, not Increasing; Plentiful but not a Continuous 

 Layer, H2. 



These clouds are delicate in texture, although a reproduction m 

 black and white tends to give too thick an appearance to cirrus. It 

 does not differ from the type coded as Hi, except that it is more 

 abundant over much of the sky. It does not increase in amount. 

 (Photo at Cheyenne, Wyo., by H. T. Floreen.) 



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