In 1818 the Scotch-Irish Thomas S. Stewart migrated to Philadelphia where he lived with his uncle, the master house carpenter Thomas Stewart (d. 1822). Following his uncle's death, the lad was apprenticed to Carpenters' Company member John Guilder (d. l854) for four years. Free of his articles in 1827, Stewart probably continued in Guilder's employ as a journeyman until 1829, when his surviving account book begins and he first appears in the Philadelphia city directories as a carpenter at 182 Lombard street. It is not known where Stewart received his training in architecture, but in the l83Os he began entering major architectural competitions. His drawings submitted for the Girard College (1832) and Preston Retreat (1837) competitions--both of which he lost to his contemporary Thomas U. Walter
--survive: they show him to be a competent designer and draftsman. Stewart's career as an architect began inauspiciously: his first executed design of importance was the ill-fated Pennsylvania Hall (1837-38) 6th above Cherry, that was gutted by an incendiary anti-abolitionist mob three days after it opened. The following year he successfully competed for the St. Luke and the Epiphany Church on l3th below Spruce, where his "Corinthian" design was selected over the more expensive "Gothic" proposals of both William Strickland
and John Notman
. St. Luke Church (1839-1840) marks a turning point in Stewart's career. The completed church was admired by a building committee from Richmond, VA, appointed "to visit churches in Northern cities, where the attention of the public is more directed to the science of architecture than in the South." The committeemen were so taken with Stewart's design that they invited him to Richmond to design St. Paul's Church (1843-1845). Several other public and private commissions followed in that city, most notably the Egyptianesque Richmond Medical College (1844) which remains his best known work and one of the finest surviving American examples in that style.
Although Stewart continued to appear in Philadelphia city directories as an architect (or as architect and engineer) until his death on May 4, 1889, virtually nothing is known of his career after the Richmond years. In the l85Os he served as a consultant to the City of Philadelphia, and in l854 he was employed by Philadelphia County to design an iron bridge to cross the Schuylkill River at Chestnut street. Stewart discussed this project in two publications: Report on the designs for a malleable iron viaduct across the Schuylkill at Chestnut Street (Philadelphia, 1854) and Report on the tubular arch viaduct to be constructed of malleable iron, across the Schuylkill at Chestnut Street (Philadelphia, l855). Consolidation of city and county in 1855 placed a new Schuylkill bridge under city jurisdiction, causing Stewart's design to be shelved. (During the Civil War Strickland Kneass designed a masonry bridge for the site that was erected.)
Stewart became a member of The Athenaeum of Philadelphia in 1874.