Arcus Cloud

An arcus cloud is a low, horizontal cloud formation. Roll clouds and shelf clouds are the two types of arcus clouds. A shelf cloud is usually associated with the leading edge of thunderstorm outflow; roll clouds are usually formed by outflows of cold air from sea breezes or cold fronts in the absence of thunderstorms.

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    The cloud was so dark that it needed all the bright lights that could be turned upon it. But for four years there was a contagion of nobility in the land, and the best blood North and South poured itself out a libation to propitiate the deities of Truth and Justice. The great sin of slavery was washed out, but at what a cost!
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