Keely
"On this rude harmonious trumpet this magician (Keely) blows through a small window into the next room towards a common zither some ten feet distant, held upright on a table by a small standard composed of a group of metal tubes. The two musical instruments have been carefully attuned to each other (sympathetic vibration). Attached to the back of the zither is a common silk thread loosely hanging and extending some eight feet away, where it is tied to a movable framework of half-inch iron rods, supporting and bracing in position, on an isolated table of glass, a metal globe, fifteen inches in diameter, capable of turning freely in either direction, on its axis, which bears inside the globe certain resonant tubes and plates, the table standing at an angle of 45 degrees from the face of the zither. [Dashed Against The Rock]