A trio of Highland Park’s early houses by Dallas’s society architect Hal Thomson established the aspirations of the elite as they began to populate the open prairie. The wood-framed Franklin C. and Nadine Brown Callier Jr. House (1914; 4008 Gillon Avenue) blends classical elements of pilasters and architraves within a Prairie Style body of broad overhangs and grouped windows. The Samuel and Sarah Leake House (1916; 3722 Gillon) advanced beyond the tentative style of the Callier House with an assured handling of the classical mode. The central block of the two-story stucco house is slightly recessed, fronted by an Ionic portico with a terrace above. Three second-floor arched windows are separated by pairs of engaged columns, a subtle form of Serliana.
The Lawrence A. Hart House (1917; 3801 Gillon) is an astute manipulation of numerous stylistic references into a harmonious whole. The symmetrical massing is composed of an advancing central bay with two successively receding bays on each side. The central bay is gabled, with a modest Tuscan portico and a grand arched window above. A stringcourse under the second-floor windows has the visual effect of making the first floor appear taller. The most curious effect is the thick, rolled roof edge, giving the appearance of a thatched roof.
Henry “Hal” Bowers Thomson (1882–1974) was born in Austin to a prosperous ranching family. He attended the University of Texas and MIT, traveling in Europe before returning to Dallas in 1907 to open his practice. Thomson immediately connected with the Dallas elite, joining several country clubs and marrying into a local banking family. A combination of connections and talent made Thomson a success with residential, commercial, and civic projects until his retirement in 1944.