A letter from an Oslo publication printed in PTO Magazine, 1940.
I’ll confess, I’m confused. I thought flea circuses were basically a mime act. And yet this goes into quite some detail on how to train your flea.
Were they ever…..real?

Postscript – mind blown. Here’s some British Pathe footage of a real 1940s flea circus:
“Don’t get too close. Those microbes are man-eaters!”