Detail of wool scouring machine. Metal forks pull the wool through the hot alkaline bath. Wool scouring plant, San Marcos… https://www.rawpixel.com/image/12147083/image-background-plant-personFree Image from public domain licenseEl Paso, Texas, Phelps Dodge refining company. Electrolytic tanks in which sheets of pure copper are formed. The sheets are… https://www.rawpixel.com/image/12295418/photo-image-background-pattern-woodFree Image from public domain licenseIron ore going down chute into hold of boat. Allouez, Wisconsin. Sourced from the Library of Congress. https://www.rawpixel.com/image/12284847/photo-image-person-wood-roadFree Image from public domain licenseMayetta, Kansas. Porch swing up for the winter. Sourced from the Library of Congress. https://www.rawpixel.com/image/12260662/photo-image-wood-public-domain-houseFree Image from public domain licenseWashington, D.C. Mail chute at the main post office. Sourced from the Library of Congress. https://www.rawpixel.com/image/12269296/photo-image-public-domain-factory-houseFree Image from public domain licenseJoliet, Illinois. Passing the depot and tracks of the Rock Island and Alton Railroads along the Atchison, Topeka, and Santa… https://www.rawpixel.com/image/12289841/photo-image-sky-public-domain-archFree Image from public domain license[Untitled photo, possibly related to: Loading iron ore into hold of boat. First mate directing operations. Allouez… https://www.rawpixel.com/image/12286135/photo-image-person-road-public-domainFree Image from public domain licenseCounter of main mining office at old town of Two Bit Creek, near Deadwood, South Dakota by Russell Lee https://www.rawpixel.com/image/12146498/image-person-art-vintageFree Image from public domain license[Untitled photo, possibly related to: Iron ore going down chute into hold of boat. Allouez, Wisconsin]. Sourced from the… https://www.rawpixel.com/image/12285245/photo-image-person-road-public-domainFree Image from public domain licenseClosed school in the old part of Hibbing, Minnesota. In 1919 when iron ore was found to lie under the town, many buildings… https://www.rawpixel.com/image/12286525/photo-image-plant-sky-public-domainFree Image from public domain licenseSanitary plant filter. Sonoma migratory labor camp. California. Sourced from the Library of Congress. https://www.rawpixel.com/image/12268725/photo-image-plant-person-public-domainFree Image from public domain licenseFrederiksted, Saint Croix Island, Virgin Islands. One of the cells for the insane at the Frederiksted hospital. Sourced from… https://www.rawpixel.com/image/12280086/photo-image-public-domain-wall-hospitalFree Image from public domain licenseMorenci, Arizona. Conveyor gallery where the copper is taken to the smelter, as shown in the background. Sourced from the… https://www.rawpixel.com/image/12294407/photo-image-background-public-domain-waterFree Image from public domain licenseWashington, D.C. Balcony of house being wrecked on Independence Avenue. Sourced from the Library of Congress. https://www.rawpixel.com/image/12269355/photo-image-plant-tree-public-domainFree Image from public domain licenseShenandoah (vicinity), Pennsylvania. Shaft of the Maple Hill mine as seen from the top of the shaft tower. Sourced from the… https://www.rawpixel.com/image/12275482/photo-image-public-domain-factory-houseFree Image from public domain licenseRooming house. Portsmouth, Virginia. Sourced from the Library of Congress. https://www.rawpixel.com/image/12284478/photo-image-public-domain-house-windowFree Image from public domain licenseLarge tanks used for mixing powdered gold ore with cyanide solution to extract gold and silver, gold mine, Mogollon, New… https://www.rawpixel.com/image/12171407/image-art-vintage-goldFree Image from public domain license[Untitled photo, possibly related to: Barber pole. Williston, North Dakota] by Russell Lee https://www.rawpixel.com/image/12166733/image-art-vintage-woodFree Image from public domain licenseIron ore going into hold of Great Lakes boat. First mate directing operations. Allouez, Wisconsin. Sourced from the Library… https://www.rawpixel.com/image/12286384/photo-image-person-road-public-domainFree Image from public domain license[Untitled photo, possibly related to: El Paso, Texas. Phelps Dodge refining company. Sheets of pure copper are formed by… https://www.rawpixel.com/image/12295790/photo-image-pattern-wood-public-domainFree Image from public domain licenseDimension lumber plant at Tygart Valley Homesteads, West Virginia. They cut wood to size as ordered by furniture companies.… https://www.rawpixel.com/image/12282762/photo-image-plant-person-woodFree Image from public domain licenseA searchlight next to the pilot house on the towboat Ernest T. Weir going down the Ohio River to Cincinnati. Sourced from… https://www.rawpixel.com/image/12295334/photo-image-person-public-domain-houseFree Image from public domain license[Untitled photo, possibly related to: At concentration plant iron ore is first dumped onto these shams which help separate… https://www.rawpixel.com/image/12286309/photo-image-plant-person-roadFree Image from public domain licenseBack steps of hotel. Minot, North Dakota. Sourced from the Library of Congress. https://www.rawpixel.com/image/12261854/photo-image-shadow-pattern-woodFree Image from public domain licenseNew type of plating machine being used at the Hamilton Standard Propeller Corporation. It automatically dips the part into… https://www.rawpixel.com/image/12277615/photo-image-person-technology-public-domainFree Image from public domain license