electric-filament lamp

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earthquake. Heavily damaged school in the town of Yingxiu after a major earthquake struck China's Sichuan Province on May 12, 2008.

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Space race (1957-1969) infographic between United States (U.S.) and Russia. America, Soviet Union, U.S.S.R., space exploration

Timeline of the Space Race, 1957–69

African Americans demonstrating for voting rights in front of the White House as police and others watch, March 12, 1965. One sign reads, "We demand the right to vote everywhere." Voting Rights Act, civil rights.

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Ahura Mazda - relief of the Zoroastrian god Ahura Mazda at the ancient ruins of Persepolis in Iran. Also known as Ormazd Zoroastrianism,

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Julius Caesar in full Gaius Julius Caesar (100? BCE-44 BCE) statue in Rimini, Italy. Roman general and statesman and dictator

The Time Julius Caesar Was Captured by Pirates

electric-filament lamp

lighting

Learn about this topic in these articles:

use in lighthouses

In lighthouse: Electric lamps
The electric filament lamp, which came into general use in the 1920s, became the standard illuminant. Power output ranged from about 1,500 watts for the largest structures down to about 5 watts for buoys and minor beacons. Most lamps were of the tungsten-halogen type for better…
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