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A young girl uses a door knocker to announce her presence.

Girl using a Door Knocker

A young girl uses a door knocker to announce her presence.

"The push-button...is well known in connection with the electric bell: a brass spring which forms part of the circuit closing the opening when pressed by an insulating button of hard-rubber, porcelain, or fiber,—the whole inclosed in a cap made in a great variety of ornamental designs." -Atkinson 1903

Push Button

"The push-button...is well known in connection with the electric bell: a brass spring which forms part…