Appears in 《红楼梦》 chapter 54: 大家蹑手蹑脚，潜踪进镜壁去一看 - describing characters sneaking up to peek at a mirror wall.
memory
蹑 means 'to walk softly / step lightly.' The reduplication AB-AB pattern - 'soft-foot soft-hand' - paints both hands and feet moving carefully so no sound escapes.
