Newton's Tune Analyser generating Lissajous Figures


Newton's Tune Analyser uses Lissajous figures to show that the ratio of the frequency ratios in a diatonic scale are ratios of small numbers. On one side is an airdriven vibrating harmonica reed with a small mirror attached to its free end. The octagonal rotating drum contains eight reeds, ranging up the scale from the same frequency as the fixed reed to its octave. In use, the box holding the fixed reed would be rotated 90 degrees, making it oscillate at right angles to the other reeds. A beam of light reflecting from the two reeds in succession undergoes simple harmonic motion in two perpendicular directions, thus producing a Lissajous figure when the beam strikes a screen. The shape of figures produced by the two frequencies which bear small number ratios to each other is well known. The apparatus is made by Newton & Co of London and dates from the last quarter of the nineteenth century. An identical example is in the collection of the National Museum of American History of the Smithsonian Museum (to whom I am indebted for this description) and is described as "This unique piece of Apparatus" well Early Technology is now pleased to offer a second unique example! 9.52 (24 cm) x 11" (28 cm) height 15.5" (39.5 cm)Transport at cost

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