Mute oval canceling device handstamp
This device has a wooden handle attached to a brass socket. A rubber cushion and rubber marking die with two concentric ovals was inserted into the socket. Sometimes a city and state appeared inside the inner oval. More often, there was no lettering, yielding the term 'mute oval' for this canceling device.
The tool's purpose was to obliterate postage on registered letters. Registered Mail did not have the dispatching office postmark on the envelope face during the early twentieth century, when this device was made. Instead, it appeared as a backstamp, along with the backstamps of other offices handling the mail piece in transit or the office that received it for delivery.
Mute ovals are still used occasionally, although they are seldom seen because most contemporary registered mail has either a postage meter or postal validation imprinter indicia. This handstamp style was replaced in the 1930s by a turned wooden handle with mortised socket for holding the rubber marking die.