https://creativecommons.org/publicdomain/zero/1.0/https://www.rawpixel.com/image/13970351Edit ImageSaveSaveEditCropCustom TextA ruler defending a fortress from the invading British. Gouache drawing.Original public domain image from Wellcome CollectionMorePublic DomainFree CC0 image for Personal and Business useInfoView CC0 LicenseJPEGSmall JPEG 1200 x 928 px | 300 dpiLarge JPEG 3026 x 2340 px | 300 dpiFree DownloadA ruler defending a fortress from the invading British. Gouache drawing.More