excerpt from Ragnorak, the Age of Fire and Gravel
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 lightning, 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 onto snow;
gigantic snow beds are found, which gradually solidify into ice...glaciers
intrude into all the valleys.."
 Text and illustrations from Ignatius Donnelly, Ragnorak, The Age of Fire and Gravel. Donnelly goes on to describe a post-cataclysmic era of rain and snow, followed by tremendous floods. Written in seven weeks starting in May, 1882, this 450 page book predicts the end of the world by comet impact. "I could not rest until I had written it out and then the great dread of my soul was that some accident would destroy the single copy & the world would lose a revelation," he wrote of the work.