Dr. Edward Williams of Philadelphia wished to present the university with an art building, but President Buckham was committed to developing UVM's scientific and technical disciplines and convinced him to build for the sciences instead. A Woodstock native, Williams had a distinguished career in medicine before becoming an officer of both the Baldwin Locomotive Company and the Pennsylvania Railroad. In 1885 he commissioned the railroad's architects, Wilson Brothers, to design a library for his hometown. He turned to them again for the UVM science building.
Trained as architects and engineers, John and Joseph Wilson established their office in 1875, when they won the commission for the Machinery Hall at the 1876 Philadelphia Centennial Exposition. Always abreast of developments in England and Germany, by the 1890s Wilson Brothers was a large firm noted for its innovative commercial, industrial, and educational work, including Drexel Institute in Philadelphia. The firm was familiar with UVM, having designed three professors' residences in 1891 and Converse Hall in 1895.
With its tall massing, steep roof pitches, bold cross-gabled entrance pavilion, animating dormers, and pinnacled roof ventilators, Williams Hall is a good complement to Old Mill on University Row. Deane and Woodward's University Museum (1855–1858) in Oxford, England, is a frequently cited precedent, due to the building's massing, facade organization, and Gothic character, as well as its Venetian Gothic decorative richness. This richness was achieved not by carving, as on the Oxford museum and Billings Library as well, but through Wilson Brothers' extravagant use of molded terra-cotta, even for the busts of scientists Samuel F. B. Morse, Alexander Agassiz, and Joseph Henry. The forms and decoration are close to those they utilized at Drexel. The building was progressive in its structure and mechanical systems, using fire-proof construction by the Philadelphia firm of Stacey, Reeves and Sons and including the first built-in electrical wiring at UVM.