Astounding Science Fiction July 1951 (Volume 47, Number 5)
Illustrations by Ed Cartier, Paul Orban, Hubert Rogers. Cover by Hubert Rogers (for "The End of the Line.")

Novelettes: "The End of the Line" by James H. Schmitz
"The Greatest Invention" by Jack Williamson.

Stories: "Feedback" by Katherine MacLean
"Windfall" by Catherine C. de Camp
"The Error of their Ways" by Gordon R. Dickson
"For Those Who Follow After" by Dean McLaughlin.

Science: "The Care and Feeding of Mad Scientists" by L. Sprague de Camp.

John W. Campbell's editorial is "'Evolution"; Book reviews by P. Schuyler Miller.