We obtained reasonably close control of the anti-gravity machines only about thirty years after you and I parted company, Mayor Amalfl.

Barrows does magnetic tests and finally discovers the anti-gravity machine, still on the rusted-out old truck on the nearby farm.

They rigged up a phony anti-gravity machine and told the Domerangi to duplicate it just as was done here.

Alas, Mr. Losiar died testing an anti-gravity machine he had invented soon after the last drone left Terran space.

We are trying to build a small anti-gravity machine for class.

He takes them to the Byng residence where they stay until they are able to track down the lost anti-gravity machine.

The anti-gravity machine then leaves for the 21st century and The Tar Man and Peter switch places.

Before Gideon and Nathaniel disappeared, they destroyed the anti-gravity machine.

Central to the story is the concept of a pure anti-gravity machine that turns out to be a perpetual motion machine of the 1st order.

What of Tryon Russ and his anti-gravity machine?