from The Century Dictionary and Cyclopedia
- n. The roll-clond at the front of and above an advancing squall of wind. Its formation is often the first intimation of the existence of the squall. It is most fully developed in front of a large thunder-storm cloud.
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For a long while -- for more than an hour, indeed -- it had seemed as if that black squall-cloud were lying motionless at the horizon -- an anchored ship, bulging at its wharf.
Lower away in the south -- a rare thing to come from the south in our climate -- there lay a black squall-cloud with a rounded outline, like a big windbag, resembling nothing so much as a fat boy's face with its cheeks blown out, when he tries to fill a football with the pressure from his lungs.
And the waves with the coming squall-cloud blacken.