The remarkable elastic properties of a certain platinum-iridium wire containing 40 per cent of iridium were first announced by Guthe. In his experiments the wire was used as the suspension of a torsion pendulum. Although the amplitudes of vibration were less than 50 degrees, a marked increase both in the period and in the logarithmic decrement accompanied the increase in the amplitude. Cylinders of equal mass but of different moments of inertia were suspended from the wire, set in vibration, and timed, but as a result of these experiments no change was observed in the logarithmic decrement-amplitude curves. This absence of any effect led to the supposition that the damping was proportional to the amplitude, and independent of the velocity.
Proceedings of the Iowa Academy of Science
©1910 Iowa Academy of Science, Inc.
Sieg, L. P.
"Some Recent Discoveries Concerning the Behavior of Platinum-Iridium Wires,"
Proceedings of the Iowa Academy of Science, 17(1), 185-194.
Available at: https://scholarworks.uni.edu/pias/vol17/iss1/26