Reis Receiver

Before Alexander Graham Bell many other inventors had comparable ideas. The image above is an instrument that was created by Phillip Reis. He was a physics instructor from Friedrichsdorf, Germany. When this receiver was invented everyone had the idea that it was another type of electro-magnetic receiver, but that was not the case. The receiver functioned by a hidden experiment was called magnetostriction. This reaction happens when an iron rod becomes longer or shorter when under the influence of a magnetic field. The receiver above was used for a telephone transmitter. It uses elevated levels of current, but not responsive as the common electro-magnetic receiver, but able to be understood on a call.