caption: The image shows a drawing of a machine with a large wheel on top of it, which appears to be a radiotelegraph. The wheel is cylindrical in shape and has a handle on the side for easy portability. It is surrounded by a metal frame and has several wires connected to it, suggesting that it is used to transmit signals from one device to another. The text accompanying the drawing provides further information about the machine, such as its purpose and how it works.