Electric copper kettle, with immersed element, sectioned, c 1921.

Sectioned to show element. This electric kettle (provisional patent no 33221/21) made by Bulpitt and Sons Ltd, Birmingham, was the first type of kettle to be fitted with a totally immersed heating element, doubling the efficiency of existing kettles. Earlier electric kettles had elements in a separate compartment in the bottom of the kettle, which wasted a lot of heat. This model has a traditional appearance and was used by middle class households. It was protected by patents until the mid-1930s.