A. Yes. As passing clouds screen the direct heat of the sun from the earth, they diminish the rarefication of the air also: and this is another cause why neither the strength nor direction of the wind is uniform.
Q. Would the winds blow regularly from east to west, if these obstructions were removed?
A. Without doubt they would. If the whole earth were covered with water, the winds would always follow the sun, and blow from east to west. Their irregularity is owing to the interspersion of sea and land, and the irregularities of the earth’s surface.
Q. Do winds never blow regularly?
A. Yes; in those parts of the world, where these obstructions do not exist; as on the Atlantic and Pacific Ocean, the winds are pretty uniform.
Q. What are the winds, which blow over the Atlantic and Pacific Ocean, called?
A. They are called “Trade Winds.”
Q. Why are they called trade winds?
A. Because (as they blow uniformly in one direction) they are very convenient to those who carry on trade by means of these oceans.