Yes; some clouds touch the earth, while other clouds are high up in the air.

Why are clouds higher on a fine day?

Because there is not so much moisture in the air, and, therefore, it rises higher before its vapor is condensed into clouds.

Why are clouds lower on a rainy day?

Because there is so much moisture in the air, that it is condensed into clouds near the earth.

Are the clouds high during a thunder-storm?

No; during a thunder-storm the clouds are seldom more than one-third of a mile high, and very often are much nearer the surface of the earth.

Is there any difference in the thickness of the clouds?

Yes; some are only a few inches thick, while others are a mile or more in thickness.

When the sun is about to rise, which of the seven colors of light is the first to appear?