Complex sentence: Ground was broken in early 1846, and the cornerstone was placed on 4 July; the courthouse was completed in late 1847, with the total cost of the project reaching $55,345.98.
Split into simpler sentences: Ground was broken on the new building in early 1846, and the cornerstone was placed on 4 July. The courthouse was completed in late 1847; the total cost of the structure was $55,345.98.