ing tag with each other, the air from one area flowing in upon the other much as water seeks its own level, creating fair weather and foul, and offering interesting problems to the students of navigation, not to mention variegated experiences to the flyer himself.
The nautical boys have an advantage over the avigators. Constant things like the gulf stream can be labeled and put on charts and shoals marked. But one can't fasten buoys in the atmosphere. Flyers can only plot topography. Air, like water, gives different effects under different conditions. The pilot must learn that when the wind blows over a hill from one direction, the result is not the same as that when it blows from another. Water behaves similarly. The shoals of the air seem a little more elusive, however, because their eddies are invisible. If one could see a downward current of air or a rough patch of it, avigating might be easier sometimes.
"Bumpiness" means discomfort, or a good time for strong stomachs, in the air just as rough
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