Time travel plays only a small role in Van Vogt’s three stories and a serial. The stories
follow the immortal founder of The Weapon Shops, an organization that puts science to work to
ensure that the common man is never dominated by government or corporations. Along the way, a
20th century man becomes a time-travel pawn, a young man seven millennia in the future takes
advantage of a much shorter time-travel escapade, and you’ll spot at least one other
time-travel moment.
All the stories were fixed up into two books, The Weapon Shops of
Isher and The Weapon Makers, and the SFBC gathered both those into The Empire
of Isher.