This wave information travels across the air-filled middle ear cavity via a series of delicate bones: the malleus (hammer), incus (anvil) and stapes (stirrup).
This is one of only 167 built during its production run, and it comes with a matching fitted luggage set, a hammer, and sales literature from when it was new.
Hammer interrupters were not capable of interruption rates over 200 breaks per second, and the ones used on powerful coils were limited to 20 40 breaks per second.
