Inside is a mechanical gyroscope turning at over 4,000 RPM, a filter made of germanium to block visible light, and a photoresistor. It’s sobering to think you can get all of this in a few small ...

The gyroscope was hydraulically driven off the motor, and it took three full minutes to wind its way up to 6,000 RPM, so it’s not intended for quick getaways. But the gyro would keep spinning ...