Stewart was born on March 16, 1870. He studied astronomy under William Wallace
Payne at Carlton College (Goodsell Observatory), Northfield, Minn. In April
1896 he became a staff member at Harvard College Observatory (under the directorship
of Edward Charles Pickering). From 1898-1901 he
worked at Harvard's Arequipa station using the 24" f/5.6 Bruce photographic
refractor, made by Alvan Clark & Sons and completed in 1893 (later moved
to Boyden Station at Bloemfontein, South Africa) . On August 18, 1901 he discovered
asteroid (475) Ocllo on a Bruce plate. His observations of nebulae (followed
by Royal Frost) using 4 hour-plates were published
in the Harv. Ann. 60, 156 (1908). He discovered 672 new objects, included
in the IC II (1908). After his time at Arequipa he went to Cincinnati Observatory.
But in 1910 Stewart eventually lost his job over his persistent attempt to
persuade the observatory to adopt astrophotography. As a consequence he founded
a new (amateur) organisation, the Cincinnati Astronomical Society (CAS), being
its president till his death on February 2, 1941. In his later years he was
specially known as a lecturer in astronomy. In 2000 a new 27" reflector
of the CAS was named "DeLisle Stewart-telescope".
Obituary: PASP 53, 139 (1941)
