https://creativecommons.org/publicdomain/zero/1.0/https://www.rawpixel.com/image/13967526Edit ImageSaveSaveEditCropCustom TextSmithsonian Institution, Washington, D.C. Coloured steel engraving by R. Metzeroth.Original public domain image from Wellcome CollectionMorePublic DomainFree CC0 image for Personal and Business useInfoView CC0 LicenseJPEGSmall JPEG 1200 x 866 px | 300 dpiLarge JPEG 3117 x 2250 px | 300 dpiFree DownloadSmithsonian Institution, Washington, D.C. Coloured steel engraving by R. Metzeroth.More