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.
Medical Induction Coil
This is an early medical induction coil or electrotherapy device from around 1880s. An induction coil or "spark coil" is a type of electrical transformer used to produce high-voltage pulses from a low-voltage direct current supply. Voltage is repeatedly interrupted by a vibrating mechanical contact called an interrupter . They were widely used in medical electrotherapy devices from the late 1800s to the 1920s. To operate one needs to attach a battery to the two brass terminals. This is one of the more interesting and decorative examples with brass turnings all in the original case... $1200