Rensselaer Semi-Weekly Republican, Volume 38, Number 77, Rensselaer, Jasper County, 22 June 1906 — Radium Clock. [ARTICLE]

Radium Clock.

We can not say that perpetual motion has actually been discovered, but the radium clock comes very near to it. A small quantity of radium is put in a glass tube, at the lower end of which Is an electroscope with two long strips of silver. The activity of the radium induces the “minus beta” rays to be conducted to the tips, when the leaves of the electroscope expand and touch the sides of two conducting wires. Of course, the currents are at once released and the leaves fall back again. The beats are repeated every two minutes, and the caluculation is that it will continue for no less than 30,000 years, which is about as near to perpetuity as any one need trouble about.