"On the ocean liner Mauretania, two European scientists with a dramatic new invention are barely rescued from abduction by the Van Dorn Detective Agency's intrepid chief investigator, Isaac Bell. Unfortunately, they are not so lucky the second time. The thugs attack again-and this time one of the scientists dies. What are they holding that is so precious? Only something that will revolutionize business and popular culture-and perhaps something more....

Compares the appearance and use of common machines such as camera, clock, telephone, bicycle, auto, train, and plane with that of the models used long ago.

Encourages and fosters the spirit of invention by describing how to build such gadgets as a homemade motor, a hat with a fan in it, and a motorized shoe buffer.

Three sixth-grade boys band together to build an experimental aircraft, enduring social and practical difficulties in the process.

Briefly introduces major inventions from ancient times to the present, in each field of endeavor from measuring and manufacturing to communications and computers, and explains who invented them and under what circumstances.