STEVENS J.F.

STEVENS J.F. 25.04. 1853 West Gardiner ME/USA 02.06. 1943 Southern Pines NC/USA John Frank Stevens started his engineering career on field crews, surveying mills and industrial canals. In 1873 he went to Minneapolis MN and advanced in 1874 to assistant city engineer. After years as a railroad engineer he was appointed chief engineer of the Isthmian Canal Commission in 1904, giving him control over both construction and engineering phases of the Panama Canal. When Stevens arrived at the Canal Zone in 1906, he found poor conditions. Equipment, largely inherited from the French, was antiquated, housing and food were inadequate, and the 17,000 labourers were demoralized by frequent outbreaks of yellow fever and malaria. Stevens immediately reorganized the work force and the engineering staff. Recognizing that work progress on the canal depended upon efficient transportation, he gave most time to organizing and building an extensive system of railroads to carry out the soil and rock from the Culebra Cut at the interoceanic divide. Although he had at first favoured a sea-level canal as previously made for Suez Canal, he was soon convinced that only a locked canal was feasible. In his 1906 Report, he therefore concurred with the minority opinion in opposing a sea-level canal. To facilitate construction, he successfully reorganized the Canal Commission, giving the chief engineer complete control over the Canal Zone. By the end of 1906 construction was under way but Stevens, frustrated by political manoeuvring at Washington, and eager to return to a less strenuous position, resigned a few months later. His successor, George Washington Goethals (1858-1928), later said of Stevens ‘The Canal is his monument’. Upon return to the USA he was again in railroads but from 1911 was a private consultant. He served in 1927 as president of the American Society of Civil Engineers ASCE. In 1925 a statue was erected on Marias Pass where he had earlier provided the key passage across the Continental Divide. Anonymous (1908). John F. Stevens. Journal of the Franklin Institute 165(1): 36. P Anonymous (1925). Stevens receives J. Fritz Medal. Mechanical Engineering 47(5): 383-384. P Anonymous (1939). J.F. Stevens to be given Hoover Medal. Mechanical Engineering 61(1): 97. Anonymous (1973). Stevens, John Frank. Dictionary of American biography Suppl. 3: 735-737. Scribner’s: New York. Anonymous (2000). The engineering genius history forgot. Civil Engineering 70(3): 15. P Stevens, J.F. (1927). The Panama Canal. Trans. ASCE 92: 946-967. Stevens, J.F. (1936). An engineer’s recollections. McGraw-Hill: New York. P

STEWART C.B. 08.03. 1868 Fairbury IL/USA 02.09. 1951 Anchor IL/USA Clinton Brown Stewart obtained the CE degree from Cornell University, Ithaca NY, in 1890. He was then from 1893 to 1898 professor of civil engineering at the Colorado State School of Mines, Golden CO, from when he was US assistant engineer until 1900. From 1903 to 1908 he was researcher in hydraulics at the University of Wisconsin, Madison WI, from when he continued as a private consultant until his retirement at Madison WI. Stewart was recipient of the Octave Chanute Medal of the Western Society of Engineers, and of the Fuertes Medal of Cornell University. He published numerous books, reports and papers. He was member of the Western Society of Engineers, whose headquarters were in Chicago IL, and of the American Society of Civil Engineers ASCE. During his stay at the University of Wisconsin, Stewart became known as excellent experimenter in hydraulics. His first work referred to centrifugal pumps, one of the pump types then under technical development. The second work describes submerged orifices and tubes, a classical topic in hydraulics, which has been investigated mainly in France during the 19th century. His fresh and accurate description of the flow processes added significantly to the engineering knowledge. It should here be stressed that the submergence effect of various hydraulic structures, including gates or weirs, is even currently not fully understood, mainly because of flow separation and the corresponding effects of turbulence. The 1916 paper deals with aspects of flood flows in rivers. This study includes the description of the failure of the Merrill Dam some 4 km upstream of Merrill City, which was to some 90% then submerged, but of which the discharge coefficient amounted to still almost 90% of the free overfall value. The increase of flood discharge due to the dam failure was also studied. Anonymous (1948). Clinton B. Stewart. Who’s who in engineering 6: 1906. Lewis: New York. Anonymous (1951). Clinton B. Stewart. Cornell Alumni News 54(5):148. Kolupaila, S. (1960). C.B. Stewart. Journal of the Hydraulics Division ASCE 86(HY1): 28. P Stewart, C.B. (1907). Investigation of centrifugal pumps. Bulletin 173. University of Wisconsin: Madison WI. Stewart, C.B. (1908). Investigation of flow through large submerged orifices and tubes. Bulletin 216. University of Wisconsin: Madison WI. Stewart, C.B. (1916). Investigation of flood flow on the Wisconsin River at Merrill WI, July 23-24, 1912. Journal of the Western Society of Engineers 21(9): 717-745.