Peter Mark Roget (1779-1869)
Roget the lexicographer was born in London in 1779 to a Swiss clergyman. In 1798 he graduated from Edinburgh University with a degree in medicine and began to practice. Roget had an extremely varied career; he worked in London, Manchester and Bristol as a doctor and then travelled through Europe working as a private tutor. In London he gave medical lectures and published essays on the anaesthetic effects of nitrous oxide or “laughing gas” as it became known. From 1827 to 1848 Roget was secretary of The Royal Society. As an inventor, Roget created the first slide rule, a tool to calculate the roots and powers of numbers, a precursor to modern methods and widely used in the teaching of mathematics until the calculator was invented.
Roget always had a fascination for words and for a long time had compiled lists of words to help his writing. This became Roget’s Thesaurus of English Words and Phrases and was his main body of work after he retired in 1840. The thesaurus was finally published in 1852. Today the use of the word “Roget’s” is seen as a generic term for a dictionary of words with similar meanings. It is widely used as a dictionary of synonyms and is regularly updated.
Source http://www.bbc.co.uk/history/historic_figures/roget_peter_mark.shtml