See T. Page, ed., The Diaries of Dawn Powell, 1931-1965 (1995), Selected Letters of Dawn Powell, 1913-1965 (1999), and Dawn Powell: Novels (2 vol., 2001); biographies by T. Page (1998) and M. S. Rice (2000).
Coniferous, nonevergreen tree (Metasequoia glyptostroboides), the only living species of the genus Metasequoia, of the family Taxodiaceae, native to remote valleys of central China. Both branchlets and leaves grow out in pairs from points along the stem. The bright green, feathery leaves turn reddish brown in autumn. Though Metasequoia fossils are abundant, the tree was thought to be extinct until living specimens were discovered in the 1940s. Only a few thousand are known to have survived, in central China. Since these stands were discovered, seeds and cuttings have been planted throughout the world.
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Former name of a genus of ancestral horses, commonly called dawn horses, that flourished in North America during the Early Eocene Epoch (54.8–49 million years ago). It is now classified with European species in the genus Hyracotherium. Eohippus stood 1–2 ft (30–60 cm) high at the shoulders and was adapted to running, with hind legs longer than the forelegs. The body was lightly constructed, with slender legs and elongated feet that were functionally three-toed (though the front feet had four toes). The skull varied from shortened (primitive) to relatively long (more horselike).
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Dawn refers to the twilight before sunrise. It is recognized by the presence of weak sunlight, while the sun itself is still below the horizon. There are also more technical definitions of dawn, including the following: Astronomical dawn : the moment after which the sky is no longer completely dark, formally defined as the time at which the sun is 18 degrees below the horizon in the morning. Nautical dawn: the time at which there is just enough sunlight for the horizon and some objects to be distinguishable, formally defined as the time at which the sun is 12 degrees below the horizon in the morning. Civil dawn : that time at which there is enough light for objects to be distinguishable and that outdoor activities can commence, formally defined as the time at which the sun is 6 degrees below the horizon in the morning.
Dawn should not be confused with sunrise, which is the moment when the leading edge of the sun itself appears above the horizon.