Charles Crocker, one of the “Big Four” owners of the Central Pacific Railroad, brought the power of nitroglycerine to California. He had taken on the greatest engineering challenge of the century. Beginning in 1863, he marshaled the men, money and equipment to build the transcontinental railroad eastward from Sacramento. By early 1867, more than ten thousand Chinese laborers were at the difficult and dangerous work of digging, blasting, and grading the route. But at the summit, Crocker’s men were falling behind schedule. Using black powder, the Chinese could advance the face of Tunnel Number Six through the solid granite at a rate of only 1.18 feet per day. The success of the entire enterprise hinged on completing the 1,659-foot tunnel that year.
Crocker brought English chemist James Howden to the tunnel site. Howden set up a rudimentary nitroglycerine factory, using an old kettle beneath a shed roof supported by four posts. Mixing the chemicals, he worked alone, surrounded by red flags. He taught the Chinese how to handle and use nitroglycerine for blasting. In November, the first train rolled through the summit tunnel.