https://www.usa.gov/copyrighted-government-workshttps://www.rawpixel.com/image/12275710Edit ImageSaveSaveEditCropCustom TextMake it Yours.Remix, add effects & personalize with your own textCustomizeOr start from these designsShenandoah (vicinity), Pennsylvania. A compressed air engine approaching with a train of cars in the Maple Hill mine. The pipes beside the track carry eight hundred pounds and there are valves for refueling every quarter mile. Compressed air is piped down from the surface. Sourced from the Library of Congress.MoreShenandoah (vicinity), Pennsylvania. A compressed air engine approaching with a train of cars in the Maple Hill mine. The pipes beside the track carry eight hundred pounds and there are valves for refueling every quarter mile. Compressed air is piped down from the surface. 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 1200 x 909 px | 300 dpiLarge JPEG 3500 x 2651 px | 300 dpiBest Quality JPEG 8480 x 6424 px | 300 dpiTIFF 8480 x 6424 px | 300 dpi | 103.93 MBFree Download