Humboldt traveled extensively in Latin America, exploring and describing it for the first time in a manner generally considered to be a modern scientific point of view between 1799 and 1804.

This memorable expedition may be regarded as having laid the foundation of the sciences of physical geography and meteorology. By his delineation in 1817 of "isothermal lines", he at once suggested the idea and devised the means of comparing the climatic conditions of various countries.

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