To attract attention of the visitors to the Electricity Exhibition held at Philadelphia, the Edison Electric Lighting Company devised the original idea of having their address cards distributed by a tall African-American wearing a helmet to which an Edison lamp had been fastened. The lamp on the helmet was connected to two wires concealed below his garments which led to two copper plates fitted under the heels of his boots. Other copper plates embedded in the ground were connected to the poles of a dynamo-machine used for the lighting system. Whenever both his heels were resting on two of these plates he could, by a barely discernible movement, connect or disconnect the flow of electricity to the lamp on his head, thus lighting or extinguishing it without using his hands which were needed for distributing the address cards. | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Science Source |
Bildgröße: | 2787 px × 4200 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |