558 



SCIENCE OF AGRICULTURE. 



Part II. 



electricitv. TIi first successful attempt to arrange the diversified forms of clouds, under 

 a few general modifications, was made by Luke Howard, Esq. We shall give here a 

 brief account of his ingenious classification. 



2357. The simple modifications are thus named and defined: 1. Cirrus, parallel, 

 flexuous, or diverging fibres, extensible in any or in all directions {Jig. 207. a) ; 



207 







/ 



2. Cumulus, convex or conical heaps, increasing upwards from a horizontal base (b) ; 



3. Stratus, a widely-extended, continuous, horizontal sheet, increasing from below (c). 



2358. The intermediate modifications which require to be noticed are, 4. Cirro-cumulus, 

 small, well defined, roundish masses, in close horizontal arrangement (d) ; 5. Cirro- 

 stratus, horizontal, or slightly inclined masses, attenuated towards a part or the whole of 

 their circumference, bent downward or undulated, separate, or in groups consisting of 

 small clouds having these characters [e). 



2359. The compound modifications are, 6. Cumulo-stratus, or twain cloud ; the cirro- 

 stratus, blended with the cumulus, and either appearing intermixed with the heaps of the 

 latter, or superadding a wide-spread structure to its base {/)', 7. Cumulo-cirro-stratus, 

 or Nimbus ; the rain-cloud, a cloud or system of clouds frqm which rain is falling. It 

 is a hoi izontal sheet, above which the cirrus spreads, while the cumulus enters it laterally 

 and from beneath {g, g) ; 8. The Fall Cloud, resting apparently on the surface of the 

 ground (Ji). 



