Make: Volume 75

Make a miraculous Marangoni soap boat

Victorian Toys and

Flatland Rockets

Written and illustrated by Bob Knetzger

BOB KNETZGER is a designer/

inventor/musician whose award-

winning toys have been featured on

The Tonight Show, Nightline, and

Good Morning America. He is the

author of Make: Fun!, available at

makershed.com and fine bookstores.

B

Here’s an update of a Victorian plaything. Cut

out the fish on the dotted line and float it on a

pan of water. Place a single drop of olive oil in

the circle. The oil quickly spreads out the slit

and across the water. The fish “swims” in the

opposite direction, like an exhaust-spewing

rocket subject to Newton’ ...