The cover is glass with the various Bell emblems etched on them. When it is working right, you push the button and it steps up all the way. It then starts swiping over. Each side step increases the light intensity 10%. You can push the button to stop the light on the leval you want.
It currently has a loose connection on the power supply. To fix it I need to remove some glass, One of the panels had been removed and symbolically broken (retiree died before retirement).
Eventually I will replace the glass, dust and tighten the inside and rig A John Infurna Lampshade on it.,
Jim