William Wallace (mathematician)

William Wallace was a Scottish mathematician and astronomer, born in Dysart, Fife, on 23 September 1768. He had no formal schooling after the age of eleven, worked as an apprentice bookbinder until his family moved to Edinburgh in 1784, and later wrote textbooks for his students at the Military College. He invented the eidograph, an improved pantograph, and worked on geometry; the line often called the Simson line first appears in a paper of his in 1799. He was also asked to write articles for the Encyclopaedia Britannica and the Edinburgh Encyclopaedia. He died in Edinburgh on 28 April 1843.