The Oxford Electric Bell is one example. A similar mechanism is used in the electric bell. At least two British mine explosions were attributed to an electric bell signal system. The ringing current originally operated an electric bell. The crossing was at ground level and was provided with an electric bell for safety. An electric bell system was provided for communication between guard and driver. The Oxford Electric Bell does not demonstrate perpetual motion. The driver, guard and fireman communicate with each other by an electric bell system. A year later, in 1937, the electric bell system was first installed. This cell achieved very quick success in telegraphy, signalling and electric bell work. Other embellishments included an electric bell system, marble bureaus, steam heating, and gas lighting.