Democratic Sentinel, Volume 18, Number 23, Rensselaer, Jasper County, 22 June 1894 — The Formation of Clouds. [ARTICLE]

The Formation of Clouds.

Clouds are simply a form of water made visible by the cooling of the air which previously held the water in the form of invisible vapor. Every cloud may be regarded as the top of an invisible warm column or current thrusting its way into a colder body of air. The comparative altitude of a cloud may be judged, when there is no time or opportunity to make exact measurements from its form and outline, its shape and shadow, its apparent size and. movement, its perspective effect, and the length of time it remains directly illuminated after sunset. By the last method Mr. Inwards states that some clouds have been estimated to have been at least ten miles above the surface of the earth. The cloud velocities at high altitudes have been carefully noted at the Blue Hill Observatory in Massachusetts, and show, practically, that about five miles in height the velocities are three times as fast in summer and six times in winter as the velocities of the currents on the earth’s surface.— [Knowledge. Of the population of India, 52,000,000 are engaged in agriculture.