What is the palace of green porcelain?

The TT comes up with a decidedly human plan to defeat the Morlocks, using three staples of early man: one is shelter (the Palace of Green Porcelain). The TT finds the Palace of Green Porcelain falling into ruins. Inside, he finds a long gallery that functions as a museum, with skeletons of extinct creatures and a few surviving objects from the TT's time.