Heimdall rides his horse over the rainbow bridge and blows his horn to warn the gods of the end of the world.  From Tales from the Far North by Maria Klugh, 1909. 

"Smog without filter tip," "clouds of fear," "strange rain of cranberry juice."  From The Gateway, 1960.

"Jupiter and Venus are coming toward us."  From The Children's Newspaper, 1944.

"How do we know we are in the 'last days'?"  From Awake Magazine, 1968.

"Apocalyptic Key: The Seven Seals of St. John” from Dogme et Rituel de la Haute Magie by Eliphas Levi, 1896.  Via Visio Smaragdina.

"Worlds without end.  How will the end of ours come?"  From The Children's Newspaper, 1935.

From Duke University Medical Center's 1964 yearbook.

From Psychic and UFO Revelations In The Last Days by Timothy Beckley.

The table of contents in Eastern Pentecostal Bible College's 1965 yearbook is titled, "God's End-Time Program."

From Amazing, 1928.

"Urgent!  Doors closing."  From Southern California Bible College's 1953 yearbook.

"Twenty minutes against eternity."  From The Children's Newspaper, 1921.

From Tales From Silver Lands by Charles J. Finger and illustrated by Paul Honoré, 1924.

From The Children's Newspaper, 1931.

From The World Goes Smash by Samuel Hopkins Adams.

Uh-oh: "Eventually, the world will die out and become a dry barren thing with no life upon it."  From Other Worlds Than This by Elena Fontany and illustrated by John Dukes McKee, 1930.

This yearbook kicked off with the apocalypse.  From St. Louis University's 1935 yearbook.

"(There is always a last time for everything.)  Overhead, without any fuss, the stars were going out."  From "The Nine Billion Names of God" by Arthur C. Clarke.

"It's all over now."  From The Film Daily, 1927.