Essays on the anatomy and philosophy of expression / By Charles Bell. https://www.rawpixel.com/image/13994876/essays-the-anatomy-and-philosophy-expression-charles-bellFree Image from public domain licenseThe anatomy and philosophy of expression as connected with the fine arts / By Sir Charles Bell. https://www.rawpixel.com/image/13972460/image-cartoon-face-personFree Image from public domain license