A construction photograph of one of the spectacular stretches of railroad construction in the United States--the first line between San Francisco and Los Angeles--finished in 1876. Nine men stand dwarfed at the entrance of the tunnel, with four men standing below. The rest of the image is taken up with tunneling debris and the vast mountainside. Even as technology advanced rapidly in the 19th century, brute labor was required to accomplish many seemingly insurmountable tasks such as tunneling through solid rock on a mountainside. The work was not random; a surveyor stands on the right, making sure of levels. Photographing men in drab work clothes against a drab mountainside results in a monochromatic image that requires close viewing to interpret.