https://creativecommons.org/publicdomain/zero/1.0/https://www.rawpixel.com/image/13982834Edit ImageSaveSaveEditCropCustom TextMiddlesex House of Correction: male prisoners treading on the boards of a treadmill: in the foreground others sit resting. Wood engraving by W.B. Gardner, 1874, after M. Fitzgerald.Original public domain image from Wellcome CollectionMorePublic DomainFree CC0 image for Personal and Business useInfoView CC0 LicenseJPEGSmall JPEG 826 x 1200 px | 300 dpiLarge JPEG 2267 x 3293 px | 300 dpiFree DownloadMiddlesex House of Correction: male prisoners treading on the boards of a treadmill: in the foreground others sit resting. Wood engraving by W.B. Gardner, 1874, after M. Fitzgerald.More