Alexander von Humboldt, Carte Générale du Royaume de la Nouvelle Espagne…, 1811

“undoubtedly the most important and most accurate published map that had yet appeared for the area of the American West which it included.” — Carl Wheat

Alexander von Humboldt completed his landmark map of New Spain in 1808. This rare and important map was published in the atlas that accompanied his Essai Politique sur le Royaume de Nouvelle Espagne in 1811. The map, in fact, was quite influential even before it was published, as both Zebulon Pike and Aaron Arrowsmith had access to it in the preparation of their important maps. Humboldt’s work was among the first to establish the field of geography as a modern science, and it was immediately translated into several European languages. The map of New Spain instantly established itself as the model for maps of the region, which includes all of Texas, New Mexico, Arizona, Colorado, Nevada, and parts of Wyoming, Kansas, Utah, Mexico, and California.

One of the greatest scientists of all time, Humboldt spent five years between 1799 and 1804 exploring Spanish America, a region mostly unknown in Europe in the late 1700s. As a world-famous scientist, Humboldt had royal patronage and had been granted access to the Spanish archives in Mexico that were generally off-limits to foreigners. His privileged status thereby enabled him to consult documents produced by explorations from the time of Oñate (1598-1610) to Escalante (1776). Humboldt’s map of New Spain drew much information from Bernardo de Miera y Pacheco’s map of the Dominguez–Escalante Expedition. With the material he collected, Humboldt created an unprecedented study of Texas and the Southwest. He compiled his information in the two-volume publication Essai Politique and Atlas Géographique, which proved to be a foundational work in the field, covering the area’s physical and economic geography, social structure, and statistical measures. Perhaps most importantly for some of its European audience, the work presented a significant record of New Spain’s mineral wealth. At a time when Mexico was the uncontested world leader in silver production, Humboldt’s publication provided reliable data on the area’s mineral resources and its trading potential, while his map was of special value for its display of information that had never before appeared in print.

Humboldt brought modern scientific techniques to bear on the project by coordinating all the points fixed by astronomical observations contained in the reports. He was also able to arrive at altitude measurements through the use of the barometer, a technique he learned from the esteemed mathematician, Pierre-Simon Laplace. In fact, in the process of preparing this visually striking map, Humboldt advanced an innovation in mapping iconography that would be lasting. As Wheat observed, “Humboldt performed a service to all concerned with the science of cartography when he adopted the ‘hachure’ method of showing mountains in place of the older and much less satisfactory method of representing mountains in profile.”

Although Humboldt’s map was epochal for its depiction of the Southwest, it also perpetuated errors from earlier American and Spanish sources, particularly distortions of Texas geography derived from Alzate’s 1768 map of New Spain. Overall, however, the map was a superb cartographic achievement and it served as a model for most European cartographers of the period.

“Humboldt’s bitter charges against Aaron Arrowsmith, and rather gentle chiding of Pike, for copying without credit from the Carte Générale, Arrowsmith in his New Map of Mexico, London, 1810 (entry No. 1046), and Pike in his Account of Expeditions to the Sources of the Mississippi, Philadelphia, 1810 (entry No. 1047), should be mentioned. … Now that it seems to be fairly well established that the Humboldt Carte Générale was actually published in 1809, or a year or so before the Arrowsmith New Map of Mexico, there is no longer a problem of how it was available for use by Arrowsmith, as we do not have to speculate as to how Arrowsmith had access to the manuscript copy that Humboldt left with our State Department in the spring of 1804.” — Thomas W. Streeter

Refs.: Howes, H786; Martin and Martin, Maps of Texas and the Southwest, plate 23; Rumsey, no. 0328.001 and 0328.002; Streeter, Bibliography of Texas, part III, vol. 1, no. 1042; Wheat, Mapping the Transmississippi West, vol. I, no. 273.