The original caption for this photo states that these are National Park Service Workers. Standing in front of a Texas oil derrick, the workers have loaded oil barrels on a mule-drawn wagon. The image serves as an example of the rise of Texas oil industry. | Creator: Unknown | Date: Unknown. | Source: Located on the National Park Service article on oil and gas, which credits original source to Lamar University Archives and Special Collections. History of the Oil & Gas Industry - Big Thicket National Preserve (U.S. National Park Service) (nps.gov) | Rights: Image available on the Internet and included for instructional purposes in accordance with Title 17 U.S.C. Section 107.Download Original File