Because the earthen vessel is a good radiator, and gives off the heat of the water rapidly.
If the bright tin vessel be painted, will the water keep hot so long?
No; the tin becomes a good radiator when painted, and the water is soon cooled.
Why does a stove cool so quickly?
Because the iron is a good radiator, and gives off its heat rapidly.
Do the rays from the sun give off much heat while passing through the air?
The rays from the sun give off about one-fourth of their heat while passing through the air.
What becomes of the remaining heat from the sun?
It is absorbed or reflected at the earth’s surface.
What does the earth do with the heat?