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Aphrodite. Greek mythology. Sculpture. Aphrodite is the Greek goddess of love and beauty.

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American bison (Bison bison) also known as buffalo or plains buffalo on the prairie, western U.S.

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Andrew Jackson delivering a speech while on his way to Washington, D.C., for his inauguration in 1829. From Harper's Weekly, 1881.

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Wolfgang Amadeus Mozart. Mozart rehearsing his 12th Mass with singer and musician. (Austrian composer. (Johann Chrysostom Wolfgang Amadeus Mozart)

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cloning. First cloned cat. First cloned companion animal. CC (copy cat) female domestic shorthair cat (b. Dec. 22, 2001) photo Jan. 18, 2002. Cloned at Texas A&M Univ. College of Vet. Med. & Biomedical Sciences. Reproductive cloning genetics DNA cc cat

CC, The First Cloned Cat

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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rock drill

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innovations in rock-drilling

In drilling machinery
The first patented rock drill was invented in 1849 by J.J. Couch of Philadelphia. Its drill rod passed through a hollow piston and was thrown like a lance against the rock; caught on the rebound by a gripper, it was again hurled forward by the stroke of the…
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pneumatic device

In pneumatic device: Major types of pneumatic devices
Rock drills are used for mining and rock excavation. An example of such a pneumatic tool is the hammer drill, or percussion hammer, which is composed of a piston and a drill made of high-carbon steel. The drill is held loosely in a chuck at…
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