An isothermal map of the world, based on the research of Alexander von Humboldt, a German naturalist whose work laid the foundation for the sciences of physical geography and meteorology, among other things. By delineating "isothermal lines", he simultaneously suggested the idea and devised the means of comparing the climatic conditions of various countries.Map: William C. Woodbridge; Restoration: Jujutacular and Lise Broer
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