Alfred Walter Stewart (1880–1947) was a distinguished British chemist and author of the popular textbooks Recent Advances in Organic Chemistry (1908) and Recent Advances in Physical and Inorganic Chemistry (1909). Via a 1918 theory of the physical chemistry of radioactivity, he contributed the term isobar — as complementary to the term isotope — to science. Under the pseudonym J. J. Connington, Stewart wrote seventeen well-received detective novels; Nordenholt's Million is his only science fiction novel.