https://creativecommons.org/publicdomain/zero/1.0/https://www.rawpixel.com/image/14001229Edit ImageSaveSaveEditCropCustom TextJohn Tyndall. Photograph by Elliott & Fry.Original public domain image from Wellcome CollectionMorePublic DomainFree CC0 image for Personal and Business useInfoView CC0 LicenseJPEGSmall JPEG 788 x 1200 px | 300 dpiLarge JPEG 1263 x 1924 px | 300 dpiFree DownloadJohn Tyndall. Photograph by Elliott & Fry.More