Harmonic Motion of Rotation Apparatus

ca 1910

With a Harmonic Motion of Rotation Apparatus, students could verify the laws of harmonic motion. The “Gurley” inscription on one leg of this example refers to W. & L. E. Gurley, the Troy, N.Y. firm that specialized in surveying instruments, and that produced physical and scientific instruments for a few years in the early twentieth century. Gurley boasted that this instrument “is simple in design and compactly built. The horizontal aluminum circle is graduated in degrees. The vertical axis is supported on cone bearings. The inertia may be varied by shifting the weights on the horizontal arms. The laws of simple harmonic motion are verified by noting a number of successive readings of the pointer on the scale.” New, it cost $22.