Enchiridion: or A Hand for the One-Handed

Captain George Webb Derenzy (1786-1871), author of Enchiridion, had his right arm amputated when he was wounded by a cannon shot at the Battle of Vitoria in 1813. Thereafter he worked to find ways to make life more manageable for himself and others by inventing or improving upon tools to aid the one-handed. Among the devices discussed in his book are a shaving box, boot hooks, and an ivory vice with a ball and socket. Derenzy also described the methods for tasks such as stropping a razor and tying a cravat using one hand.