This Holcomb Annunciator, nicknamed "The Thumper," was early acoustic unit used in the 1880s to send voice transmissions from one room to another. The term "Thumper" comes from the sound the unit makes when you tap your knuckle on it to get the attention of someone in another room. Once you had their attention you could then send a voice transmission between two locations. A stranded steel wire was strung tightly between the units, much like the "two cans and a string" technology. This unit was used in the Frank Mitchell residence on Denny Hill Road in Warner NH, and donated by his grandson, Francis Mitchell, Contoocook, NH.

New Hampshire Telephone Museum
Warner, NH