United States. Signal Office. *Cab.39.31 4 Charts showing the average monthly cloudiness in the United States. [Washington. r1&g1.] (2) pp. (12) charts, each 47% X 60 cm., folded once and mounted in covers. “The data have been drawn from eighteen years’ tri-daily eye observa- tions, 1871-1888.”
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This card was printed at the Boston Public Library, April 14, 1914.
K1917 — United States. Meteor. — Clouds.