Sir Isaac Newton. Line engraving by E. Smith, 1821, after Sir G. Kneller, 1702. https://www.rawpixel.com/image/13987000/sir-isaac-newton-line-engraving-smith-1821-after-sir-kneller-1702Free Image from public domain licenseSir Isaac Newton. Stipple engraving by E. Scriven after L. Allen after L. F. Roubiliac. https://www.rawpixel.com/image/14012298/image-face-person-artFree Image from public domain licenseSir Isaac Newton. Line engraving by Caroline Hulot [] after E. Seeman, 1726. https://www.rawpixel.com/image/13984015/sir-isaac-newton-line-engraving-caroline-hulot-after-seeman-1726Free Image from public domain licenseSir Isaac Newton. Line engraving by A. de St Aubin after himself after J. Roettiers, 1739. https://www.rawpixel.com/image/13991637/image-face-person-artFree Image from public domain licenseSir Isaac Newton. Line engraving after J. Vanderbank, 1720. https://www.rawpixel.com/image/14003729/sir-isaac-newton-line-engraving-after-vanderbank-1720Free Image from public domain license