The Courthouse was a large, imposing Italianate structure featuring 14 statues representing various Roman Goddesses including Minerva, Flora, Ceres, Fortuna, and Juno. The statues were made of zinc and painted over grey with grey colored sand to appear stone-like. In 1893, a clock was added to the tower, similar to a clock installed on a courthouse in Santa Rosa. The building became a mainstay in the community as a number of local groups used the massive staircase in front of the courthouse to stage group photos. Many of these large group photos are currently on display as part of the Fraternal Orders of Humboldt County exhibit.
Nevada State Journal, Reno, NV 7 Sept 1924
Courthouses of California: An Illustrated History by Ray McDevitt
Humboldt County Historical Society as cited here
You can see more photos of the courthouse here at "Courthouse History"