Wikipedia has a nice photo of the old Post Office. U.S. Post Office and Customhouse in 1903. Completed in 1882. Supervising Architect: Alfred B. Mullet The U.S. District Court for the District of Connecticut met here until 1933. The building was razed in 1934. The Post Office is currently housed across the street, next to the FNB building.
Panoramio has a good photo of the surviving facade of the old First National Bank building. More on Hartford’s old FNB building from Historic Buildings of Connecticut. Designed by Ernest Flagg and completed in 1899, the Beaux Arts-style First National Bank building had a fireproof construction consisting of steel structural columns and cinder-covered brick vaults under the floors. The facade of the building has survived to become part of State House Square.
Kashmann’s (with much of the extra advertising, shown in the 1903 photo, removed.)