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Amendments 1-10 to the Constitution of the United States constitute what is known as the Bill of Rights on an American flag.

What Is the Emoluments Clause?

Aspirin pills.

7 Drugs that Changed the World

Figure 13: A Maxim machine gun, belt-fed and water-cooled, operated by German infantrymen, World War I.

7 Deadliest Weapons in History

Periodical Cicada, Adult, Magicicada spp. Requires 17 years to complete development. Nymph splits its skin, and transforms into an adult. Feeds on sap of tree roots. Northern Illinois Brood. This brood is the largest emergence of cicadas anywhere

Why Do Some Cicadas Appear Only Every 17 Years?

Gutzon Borglum. Presidents. Sculpture. National park. George Washington. Thomas Jefferson. Theodore Roosevelt. Abraham Lincoln. Mount Rushmore National Memorial, South Dakota.

9 Memorials and Monuments in the United States

Aurochs. Bos primigenius. Skeleton. Extinct animal. Skeleton of an Aurochs, an extinct wild ox.

6 Animals We Ate Into Extinction

Drinking water is poured into a glass.

Water Fluoridation: Just the Facts

silk

in sapphires

Learn about this topic in these articles:

result of sapphire inclusions

In sapphire
…faint whitish sheen, known as silk. Tiny, regularly arranged mineral inclusions (commonly rutile) and elongate cavities are responsible for the asterism shown by star sapphire.
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