A Windermere kettle[1] is a form of steam-operated tea urn or samovar installed on some steam launches.
[3] Inside the vessel is a steam heating coil.
When hot or boiling water is required, a valve is opened and steam from the boat's propulsion boiler is passed through the coil, heating the water.
Windermere kettles are rapid boilers and can heat enough water to make a pot of tea in only a few seconds.
Their name is derived from the popularity of steam launches on Windermere, a lake in the English Lakes, during the Victorian and Edwardian periods.