We have always considered and collected these commercial masks and helmets as industries tribal art. Examples can be elegant in their simplicity or bazaar and complex. They are always unique, suprising and filled with personality.
Dome Glass Galvanometer
Brass galvanometer with glass dome and wooden base with 4-screw base, instrument unsigned but could be Philip Harris Ltd Birmingham England. Made in the late 1800s, It's used as a detector of direct current and of very weak intensities.... $750