Excerpt: "Spread before you a map of South America. Fix your eye on the point of confluence between two of its great rivers—the Salado, which runs south-easterly from the Andes mountains, and the Parana coming from the north; carry your glance up the former to the town of Salta, in the ancient province of Tucuman; do likewise with the latter to the point where it espouses the Paraguay; then up this to the Brazilian frontier fort of Coimbra; finally draw a line from the fort to the aforementioned town—a line slightly curved with its convexity towards the Cordillera of the Andes—and you will thus have traced a boundary embracing one of the least known, yet most interesting, tracts of territory in either continent of America, or, for that matter, in the world. Within the limits detailed lies a region romantic in its past as mysterious in its present; at this hour almost as much a terra incognita as when the boats of Mendoza vainly endeavoured to reach it from the Atlantic side, and the gold-seekers of Pizarro’s following alike unsuccessfully attempted its exploration from the Pacific. Young reader, you will be longing to know the name of this remarkable region; know it, then, as the “Gran Chaco.””
Thomas Mayne Reid (4 April 1818 – 22 October 1883) was an Irish-American novelist who fought in the Mexican–American War (1846–1848). His many works on American life describe colonial policy in the American colonies, the horrors of slave labour and the lives of American Indians. "Captain" Reid wrote adventure novels akin to those by Frederick Marryat and Robert Louis Stevenson, and set mainly in the American West, Mexico, South Africa, the Himalayas, and Jamaica. He was an admirer of Lord Byron.