In 1900, ownership of the gatehouse was transferred from Henry Somerset, 9th Duke of Beaufort to Monmouthshire County Council as part of the disposal of the entirety of the Somersets' land holdings in Monmouthshire. The gift is recorded on a brass plaque attached to the gatehouse.[54] The local antiquarian Mary Ellen Bagnall-Oakeley wrote the first history of the bridge and gatehouse, Monnow Bridge Tower, which appeared in 1903.[65][lower-alpha 8] In April 1893, the first street light was erected on the bridge by the town council. In the late 1920s, the top portion of this light was replaced by twin electric lamps.