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Lusitania sinking, illustration from The War of the Nations (New York), December 31, 1919. World War I, WWI. This image is one of three on the page. (See source file for the other two.)

7 of the World’s Deadliest Shipwrecks

July, 2006, Launch of Space Shuttle Discovery STS-121. See attached for full caption information.

Will Light-Speed Space Travel Ever Be Possible?

Illustration for Demystified "How Dangerous is Quicksand"

How Deadly Is Quicksand?

Entrants falling and tumbling over while chasing the cheese at the 2016 'Cheese Rolling' held at Cooper's Hill, in the Cotswolds, Brockworth England

7 of the World’s Most Dangerous Festivals

Titanic infographic. The 30th anniversary of its discovery is September 1, 2015. SPOTLIGHT VERSION.

Timeline of the Titanic’s Final Hours

Battle of the Alamo from "Texas: An Epitome of Texas History from the Filibustering and Revolutionary Eras to the Independence of the Republic, 1897. Texas Revolution, Texas revolt, Texas independence, Texas history.

6 Wars of Independence

Easter Procession of Maria Santisima del Sacromonte in Granada, Spain. This statue is known as Virgen de los Gitanos or The Virgin of the Gypsies.

What is Holy Week?

air duct

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acoustic filtration

In sound: Acoustic filtration
…cross-sectional area are inserted into air ducts, as illustrated in Figure 3. The impedance mismatch introduced into a duct by a change in the area of the duct or by the addition of a side branch reflects undesirable frequencies, as determined by the size and shape of the variation. A…
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