Fig. 7.—CUMULUS, OR PILE CLOUD.
382. How are clouds affected by winds?
If cold winds blow upon the clouds, the cold condenses the vapour, turning the clouds into rain. But if warm dry winds blow upon the clouds, they rarefy the vapour to a greater degree, and temporarily disperse the clouds.
383. How do winds affect the shapes of clouds?
When winds are mild and gentle, the clouds break into small patches, and rise to a considerable height. But when the winds are cold and blustering, the clouds fly low, and roll along in heavy masses.
384. Why are east winds usually dry?
Because in coming towards England they pass over vast continents of land, and comparatively little ocean. Hence they are not loaded with vapours.