Vintage map of North America showing January and July Isotherms 1900s.

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The Harmsworth Encyclopaedia 1930s / 1940s

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Size: 3067px × 2000px
Photo credit: © Michelle Bridges / Alamy / Afripics
License: Royalty Free
Model Released: No

Keywords: 1900s, 1930s, 1940s, america, american, education, encyclopaedia, harmsworth, history, isotherms, january, july, map, maps, north, patterns, pressure, reference, showing, social, study, temperature, vintage, weather