But gradually the heat begins to dissipate. This is a signal for tremendous electrical action. Condensation commences. Never has the air held such incalculable masses of moisture; never has heaven's artillery so rattled and roared since earth began! Condensation means clouds. We will find hereafter a whole body of legends about "the stealing of the clouds" and their restoration. The veil thickens. The sun's rays are shut out. It grows colder; more condensation follows. The heavens darken. Louder and louder bellows the thunder. We shall see the lightnings represented, in myth after myth, as the arrows of the rescuing demi-god who saves the world. The heat has carried up perhaps one fourth of all the water of the world into the air. Now it is condensed into cloud. We know how an ordinary storm darkens the heavens. In this case it is black night. A pall of dense cloud, many miles in thickness, enfolds the earth. No sun, no moon, no stars, can be seen. "Darkness is on the face of the deep." Day has ceased to be. Men stumble against each other. All this we shall find depicted in the legends. The overloaded atmosphere begins to discharge itself. The great work of restoring the waters of the ocean to the ocean begins. It grows colder--colder--colder. The pouring rain turns into snow, and settles on all the uplands and north countries; snow falls on {p. 110} snow; gigantic snow-beds are formed, which gradually solidify into ice. While no mile-thick ice-sheet descends to the Mediterranean or the Gulf of Mexico, glaciers intrude into all the valleys, and the flora and fauna of the temperate regions become arctic; that is to say, only those varieties of plants and animals survive in those regions that are able to stand the cold, and these we now call arctic. In the midst of this darkness and cold and snow, the remnants of poor humanity wander over the face of the desolated world; stumbling, awe-struck, but filled with an insatiable hunger which drives them on; living upon the bark of the few trees that have escaped, or on the bodies of the animals that have perished, and even upon one another. All this we shall find plainly depicted in the legends of mankind, as we proceed. Steadily, steadily, steadily--for days, weeks, months, years--the rains and snows fall; and, as the clouds are drained, they become thinner and thinner, and the light increases. It has now grown so light that the wanderers can mark the difference between night and day. "And the evening and the morning were the first day." Day by day it grows lighter and warmer; the piled-up snows begin to melt. It is an age of tremendous floods. All the low-lying parts of the continents are covered with water. Brooks become mighty rivers, and rivers are floods; the Drift _débris_ is cut into by the waters, re-arranged, piled up in what is called the stratified, secondary, or Champlain drift. Enormous river-valleys are cut out of the gravel and clay.