Powerlite Devices Ltd. Mercury Street Lamp

Powerlite Devices Ltd. Mercury Street Lamp

Current location:

Collection Storage Facility


Ontario Hydro acquired this artifact for its Museum of Electrical Progress in the late 1960s, transferring it to the national collection in 1992.

Technical history:

Designed to dispense high-intensity lighting along major highways, the Powerlite lamp was an innovation of the 1960s. Nicknamed "The Cobra Head" because of its design, the lamp was equipped with a transformer and ballast to regulate the voltage and current. Although most have been phased out, some of these lamps continue to light up Canada’s highways today.


More efficient than incandescent and fluorescent lamps, mercury lamps, also called mercury-vapour lamps, generated an electric arc in vaporized mercury to produce light. European scientists experimented with mercury-vapour light as early as 1835. The first commercial mercury lamps were manufactured in the United States in 1901 by Peter Cooper Hewitt. Mercury-vapour lamps were applied to street lighting in 1948, and since the 1970s, have been largely replaced by sodium lamps.

Canada Science and Technology Museum
Artifact No.
Powerlite Devices Ltd.
Manufacturer Location
Toronto, Ontario
Manufacture Date
Acquisition Date