Episode: Lazy Transactions for Filesystem Meta-Data Updates

A stereoscope comprises a pair of eye pieces and an objective lens disposed on a frame. The center of the objective lens is fitted to be deviated from the optical axis of the eye piece. One or both eye pieces are slidable to the frame. The stereoscope can be replaced by a microscope body constituted by an eye piece and an objective lens, through the intermediary of a grip extended from the frame.