Before arriving in Panama, as was the practice, Olmsted started taking several grains of quinine each day, prophylactically, so as to ward off malaria. The “Chagres shakes”—named after a river that ran alongside the rail line in Panama—was a particularly virulent strain. In 1852, Ulysses Grant had lost 250 men while marching across Panama. As an old man, he’d remember the horrors of Panama more vividly than those of the Civil War.
