Bosch Make & Break Spark Plug

Here's a unique German Bosch sparkplug. It is called a make & break spark plug. It is dated from 1916. It was used in Europe for early racing autos of the time. From what I have found out on the internet, it uses a coil in the inside that builds a charge up. At the time of ignition, the electrode jumps away from the seat and throws a hot spark to fire the cylinder of the car. It uses the same type of ignition as the early hit/miss engines that had an igniter ignition. It is in "like new" condition and is about 4" long and has a 26 mm. diameter threaded end.