Synopsis: "Two cousins, on vacation in Edinburgh, meet a mysterious woman who leads them on a time travel adventure." --summary, WorldCat library record OCLC 21158580 Simon and Malcolm visit their great-uncle Henry in Edinburgh. "As youngsters, Henry and the boys' grandmother had time-slipped into old Edinburgh, bringing the box back with them to the 20th century. But misunderstanding the gravity of their mission, they failed to deliver it untouched ..." --Kirkus Reviews 1989 (undated online)