Muir went from impassioned author to leading activist. He would popularize glaciers unlike anybody else, and be to glaciers what Jacques Cousteau would be to the oceans and Carl Sagan to the starsThe book also offers an environmental caveat on global climate change and the glaciers' retreat alongside a beacon of hope: Muir shows us how one person changed America, helped it embrace its wilderness, and in turn, gave us a better world.In 2005, Californians had to choose a design for its commemorative quarter. Hundreds of submissions – the iconic Hollywood sign above Hollywood Hills, the 1849 Gold Rush, the Golden Gate Bridge, etc. – fell away until one remained: an image of John Muir.  2014 will mark the 100th anniversary of Muir’s death. Muir’s legacy is that he reordered our priorities and contributed to a new scientific revolution that was picked up a generation later by Aldo Leopold and Rachel Carson, and is championed today by influential writers like E.O. Wilson and Jared Diamond.Heacox takes us into how Muir changed our world, advanced the science of glaciology and popularized geology. How he got people out there. How he gave America a new vision of Alaska, and of itself.

    Inspired by the Enlightenment quest for knowledge, they consider it a slur on the age that the interior of Africa still remains a mystery, that maps of the "dark continent" are populated with mythical beasts, imaginary landmarks, and fabled empires. As well, they hoped that more accurate knowledge of Africa would aid in the abolition of the slave trade. These men, a mixed group of soldiers and gentlemen, ex-convicts, and social outcasts, form the African Association, the world's first geographical society, and over several decades send hardened, grizzled adventurers to replace speculation with facts and remove the beasts from the maps. The explorers who ventured forth included Mungo Park, whose account of his travels would be a bestseller for more than a century; American John Ledyard; and Jean Louis Burckhardt, the discoverer of Petra and Abu Simbel. Their exploits would include grueling crossings of the Sahara, the exploration of the Nile, and---most dramatically---the search for the great River Niger and its legendary city of gold: Timbuktu. Anthony Sattin weaves the plotting of the London gentlemen and the experiences of their extraordinary explorers into a gripping account of high adventure, international intrigue, and geographical discovery. "The Gates of Africa" is a story of human courage and fatal ambition, a groundbreaking insight into the struggle to reveal the secrets of Africa.