Mechanics: men using a dynamometer to measure forces. Coloured engraving, 1803, by J. Pass. https://www.rawpixel.com/image/13966522/image-cartoon-person-swordFree Image from public domain licenseDrop-front secretary on stand (secrètaire à abattant or secrétaire en cabinet) (one of a pair) (part of a set) https://www.rawpixel.com/image/12850815/photo-image-art-leaves-goldFree Image from public domain licensePair of Flintlock Pistols Made for Ferdinand IV, King of Naples and Sicily (1751–1825) https://www.rawpixel.com/image/12852093/photo-image-gold-wood-public-domainFree Image from public domain licenseWriters: twenty portraits of essayists and novelists. Engraving by J.W. Cook, 1825. https://www.rawpixel.com/image/14016416/image-cartoon-face-personFree Image from public domain license