Edison Mazda light bulb display stand. Super rare; perhaps only example known. Canadian patent. A double spinable lazy Susan mechanism lights one bulb at a time using a clever interior cam mechanism.Able to demonstrate eight different lamp filaments with a bulb on top that is always lit. Signed with a sweet brass plaque on original dark finish. Brass arms. Includes a “press-in” light bulb tester on the base. Original heavy wiring intact. Works just fine, but needs cam adjustments inside. 25”h x 14” diameter.