Easton's 1897 Bible Dictionary:

Gabbatha
   Gab Baitha, i.e., "the ridge of the house" = "the temple-mound,"
   on a part of which the fortress of Antonia was built. This
   "temple-mound" was covered with a tesselated "pavement" (Gr.
   lithostroton, i.e., "stone-paved"). A judgement-seat (bema) was
   placed on this "pavement" outside the hall of the "praetorium"
   (q.v.), the judgment-hall (John 18:28; 19:13).


Hitchcock's Bible Names Dictionary (late 1800's):

Gabbatha, high; elevated