Elias Anton Cappelen Smith (6 November 1873 – 25 June 1949) was a Norwegian American chemical engineer, civil engineer and metallurgist. He pioneered copper production in the early 20th century. Among his achievements were the Peirce-Smith converter[] and the Guggenheim process.
Cappelen Smith was born at Trondheim in Sør-Trøndelag, Norway. He was the son of Elias Anton Smith (1842–1912), founder of E.A. Smith AS and Ingeborg Anna Røvig (1846–1923). His middle name Cappelen is from the family of his paternal grandmother, Marie Severine Cappelen (died 1900) married to Peder Høegh Smith (died 1881). He grew up as the eldest son among nine children and attended the Trondheim Cathedral School. He was educated as a chemist at Trondhjems Tekniske Læreanstalt[], now the Norwegian University of Science and Technology, taking his final exam in 1893. The same year he emigrated to the United States.
Cappelen Smith was employed in the metallurgical industry working from 1895–96 for Chicago Copper Refining Company, during 1896–1900 for the Anaconda Copper Mining Company and from 1901–10 as head metallurgist for Baltimore Copper Smelting and Rolling Company in Perth Amboy, New Jersey. It was while at this company, that he and William H. Peirce developed the Peirce-Smith converter[], which revolutionized the Manhès-David process[].