Q. Why does a shower of rain seem to cool the air in summer-time?
A. The earth (being wet with the rain) parts with its heat to promote evaporation; and as the earth is cooled, it cools the air also.
Q. Why is linen dried by being exposed to the wind?
A. The air (blowing over the linen) promotes evaporation, by removing the vapour from the surface of the wet linen, as soon as it is formed.
Q. Why is linen dried sooner in the open air, than in a confined room?
A. Because the particles of vapour are more rapidly removed from the surface of the linen by evaporation.
Q. Why are wet summers generally succeeded by cold winters?
A. Because the great evaporation (carried on through the wet summer) reduces the temperature of the earth lower than usual, and produces cold.
Q. Why is england warmer than it used to be, when agues were so common?