The Treaty of Guadalupe Hidalgo ending the Mexican American War in 1848 included an provision guaranteeing American right-of-passage and transit across the Mexican Isthmus of Tehuantepec, viewed as the shortest practicable route across Central America, 2,400 nautical miles shorter than the route across the Panama. The California Gold Rush of 1848 brought thousands of gold seekers and soldiers across the Panamanian Isthmus, including future President Ulysses S. Grant. In the early 1850s Americans also established a regular transit path across Lake Nicaragua, which flourished until completion of the First Transcontinental Railroad in May 1869. In 1879 American engineer James B. Eads presented a scheme for a quadruple track ship-railway across the Isthmus of Tehuantepec in Mexico, while other American interests favored the old route through Nicaragua. Led by Suez Canal builder Ferdinand de Lesseps, the French set their sights on Panama in 1881 and began excavating a sea level canal in 1883, similar to that at Suez. While excavating the highlands along the Continental Divide in 1884, damaging landslides began slowing progress at Culebra and Cucaracha. Health epidemics related to outbreaks of yellow fever and malaria killed approximately 5,600 people, including 460 French engineers. The ever-increasing volume of landslides and the death toll bankrupted the enterprise and the French abandoned the project in 1889. Subsequent attempts to re-start construction met with failure in 1894, because the project was under-funded. The French then focused their efforts on selling their franchise and equipment to the United States. This sale eventually succeeded, in thanks to considerable political intrigue, Nicaraguan postage stamps portraying the Momotombo volcano, and American intervention in helping to establish Panama as a sovereign entity, separate from Columbia. Panama from they succeeded in selling their franchise to the United States in 1903, shortly Americans helped Panama separate from Columbia.