https://creativecommons.org/publicdomain/zero/1.0/https://www.rawpixel.com/image/8770523Edit ImageSaveSaveEditCropCustom TextArthur Roberts and Sam Mynatt drilling in lateral test shaft for examination of substrata at base of Norris Dam, October 1933. Photographer: Hine, Lewis. Original public domain image from FlickrMorePublic DomainFree CC0 image for Personal and Business useInfoView CC0 LicenseEditorial use only JPEGSmall JPEG 1200 x 882 px | 300 dpiLarge JPEG 3000 x 2205 px | 300 dpiFree DownloadArthur Roberts and Sam Mynatt drilling in lateral test shaft for examination of substrata at base of Norris Dam, October 1933. Photographer: Hine, Lewis. Original public domain image from FlickrMore