https://creativecommons.org/publicdomain/zero/1.0/https://www.rawpixel.com/image/14015423Edit ImageSaveSaveEditCropCustom TextGeorge Bidder, a mental calculator, aged thirteen. Line engraving by J.H. Robinson, 1819, after Miss Hayter.Original public domain image from Wellcome CollectionMorePublic DomainFree CC0 image for Personal and Business useInfoView CC0 LicenseJPEGSmall JPEG 963 x 1200 px | 300 dpiLarge JPEG 2650 x 3301 px | 300 dpiFree DownloadGeorge Bidder, a mental calculator, aged thirteen. Line engraving by J.H. Robinson, 1819, after Miss Hayter.More