https://creativecommons.org/publicdomain/zero/1.0/https://www.rawpixel.com/image/14003875Edit ImageSaveSaveEditCropCustom TextZerah Colburn, a mental calculator, as a child. Engraving, 1813.Original public domain image from Wellcome CollectionMorePublic DomainFree CC0 image for Personal and Business useInfoView CC0 LicenseJPEGSmall JPEG 727 x 1200 px | 300 dpiLarge JPEG 2100 x 3467 px | 300 dpiFree DownloadZerah Colburn, a mental calculator, as a child. Engraving, 1813.More