https://www.usa.gov/copyrighted-government-workshttps://www.rawpixel.com/image/12306770Edit ImageSaveSaveEditCropCustom TextDr. Carl C. Monrad, Consultant, Petroleum Unit, Industrial Materials, Petroleum, Chemical, and Allied Products Section, Production Division. Sourced from the Library of Congress.View public domain image source hereMorePublic DomainFree CCO U.S. Government image for Personal and Business useInfoView CC0 LicenseEditorial use only JPEGTIFFSmall JPEG 932 x 1200 px | 300 dpiLarge JPEG 2718 x 3500 px | 300 dpiBest Quality JPEG 4386 x 5648 px | 300 dpiTIFF 4386 x 5648 px | 300 dpi | 23.65 MBFree DownloadDr. Carl C. Monrad, Consultant, Petroleum Unit, Industrial Materials, Petroleum, Chemical, and Allied Products Section, Production Division. Sourced from the Library of Congress.More