They may be the two most influential scientists on the modern world whom you’ve never heard of. German naturalist and explorer Alexander von Humboldt (1769-1859) brought a modern understanding of science to lay audiences for the first time with his five-volume masterwork Kosmos, in which he sought to unify humanity’s understanding of the natural world. His elder brother, government minister, philosopher, and linguist Wilhelm von Humboldt (1767-1835) pioneered the kind of educational systems that would become the model for those used in the United States and Japan. Here, in one volume, are two monographs on the lives of the great men. HERMANN KLENCKE (1813-1881) expounds on the dramatic influence of Alexander’s work on Western thought. GUSTAV SCHLESIER covers the life of Wilhelm, with special emphasis on the politics of his era and how he used them to reform public education. Translated from the German by JULIETTE BAUER and first published in English in 1853, this hard-to-find classic offers the valuable perceptions of authors writing from the time when the authority of these two important men was beginning to be felt. Anyone interested in the history of modern science will find this perspective priceless.