A flat, circular or oval water flask traditionally carried by underground workers to stay hydrated during a shift. These canteens were typically made of aluminum or tin with a heavy canvas cover to insulate the water and protect the metal from the rough mine environment. The flat shape kept the flask close to the body, preventing it from catching on low roofs or narrow supports.
Heard on the job
Fill your Dudley before you head down the shaft, because the water station on level four is shut off.
Insider tip
Miners would often soak the canvas cover of their Dudley in water so that evaporation in the drafty mine airways would keep their drinking water cool.