 Normally, at that time, post office buildings, like all other federal government buildings, had been designed by the Office of the Supervising Architect at the Treasury Department.But the Tarsney Act of 1893 allowed a limited number of commissions, such as the 1900 Ellis Island Immigrant Inspection Center, to be awarded to private architects.Mary Thompson paid for Allen's new firm of Allen & Collens, best known for the Union Theological Seminary building on Manhattan's Upper West Side, to design the new Canandaigua post office.