of tunnels and locks. A second Isthmian exploratory visit began on December 6, 1877, where two routes were explored in Panama, the San Blas route and a route from Limon Bay to Panama City, the current Canal route. The French had achieved success in building the Suez Canal in the Middle East. While it was a lengthy project, they were encouraged to plan for a canal to cross the Panamanian isthmus. Wyse went to Bogotá and on March 20, 1878, signed a treaty, in the name of the Société Civile Internationale du Canal Interocéanique par l'isthme du Darien headed by general Étienne Türr, with the Colombian government, known as the Wyse concession, to build an interoceanic canal through Panama. French construction attempts, 1881–1899 The first attempt to construct a canal through what was then Colombia's province of Panama began on January 1, 1881. The project was inspired by the diplomat Ferdinand de Lesseps, who was able to raise considerable funds in France as a result of the huge profits generated by his successful construction of the Suez Canal. Although the Panama Canal needed to be only 40 percent as long as the Suez Canal, it was much more of an engineering challenge due to the combination of tropical rain forests, debilitating climate, the need for canal locks, and the lack of any ancient route to follow. Lesseps wanted a sea-level canal (like the Suez), but he visited the site only a few times, during the dry season which lasts only four months of the year. His men were totally unprepared for the rainy season, during which the Chagres River, where the canal started, became a raging torrent, rising up to . The dense jungle was alive with venomous snakes, insects, and spiders, but the worst challenges were yellow fever, malaria, and other tropical diseases, which killed thousands of workers; by 1884, the death rate was over 200 per month. Public health measures were ineffective because the role of the mosquito as a disease vector was then unknown. Conditions were downplayed in France to avoid recruitment problems, but the high mortality rate made it difficult to maintain an experienced workforce. Workers had to continually widen the main cut through the mountain at Culebra and reduce the angles of the slopes to minimize landslides into the canal. Steam shovels were used in the construction of the canal, purchased from Bay City Industrial