https://creativecommons.org/publicdomain/zero/1.0/https://www.rawpixel.com/image/13980415Edit ImageSaveSaveEditCropCustom TextEngineering: a polishing machine (top), and a walking machine (below). Etching.Original public domain image from Wellcome CollectionMorePublic DomainFree CC0 image for Personal and Business useInfoView CC0 LicenseJPEGSmall JPEG 1087 x 1200 px | 300 dpiLarge JPEG 2550 x 2814 px | 300 dpiFree DownloadEngineering: a polishing machine (top), and a walking machine (below). Etching.More