Balls of ultraviolet-transmitting glass containing liquid mercury, the vapor of mercury, and helium at various pressures have been spun over a wide range of rotation rates to generate light at 23°C. For the angular velocities employed, the pool of mercury exhibited no linear motion. In the case of a given ball, light was found to be emitted in a continuous discharge and sometimes in pulses of full width at halfmaximum 5 jusec as well. When the ball moves, the discharges occur between the liquid mercury and electrons trapped in surface states on the surface of the glass. The discharges assume more than one form, and their properties have been studied as a function of the rotation rate. Spectrograms of the emitted light have been observed in a quartz spectrograph. Lines have been assigned to Hg, He i, He n, C I, C n, CO, CO + , CO2, C02 + , H, Si, and B. The atomic spectral lines of Si and B are emitted from neutral atoms residing on the surface of the glass and loosely bound. In the presence of concentrated electronic surface charge, the photographed lines of Si and B exhibit a displacement to the red. The intensity of emission was noted to decrease gradually over a long period of continuous rotation of the ball.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.