 He took out the first patent in the United States for an electric action for the pipe organ when he was 20, and built the first electric action organ in the United States for the Philadelphia Centennial Exposition.Though primarily interested in the technical aspects, he had a good deal of business acumen as well, establishing factories in New York City, Philadelphia, and Baltimore.Hilborne founded the Roosevelt Pipe Organ Builders in 1870 with his brother Frank, and built some of the largest organs in the United States during his career.