The light was playing over the wet flowstone walls (I don't understand what "flowstone" means here) type of rock
Deep stone flues where the water dripped and sang (I don't understand what "flues" means here) a path or tough for the rain to flow
Its alabaster bones cast up in the shadow on the rocks behind it (I don't understand what "cast up" means here) made a shadow, "cast" a shadow
He knew only that the child was his warrant (I don't understand what "warrant" means here) under his care, responsibility
He found a good half-inch drive socket (I don't know what a "drive-socket" is) either a tool. or a place where he could place something
Finally, What is a "slutlamp"?