Where any writ which refers to a plan signed as relative thereto is presented or transmitted by post for registration in the General Register of Sasines it shall be competent to ingive to the said register along therewith a duplicate of such plan, docqueted with reference to the said writ and authenticated in the same manner as the principal plan, and such duplicate plan shall be retained in the said register. The ingiving of such duplicate plan shall be noted in the register, and acknowledgment of the receipt thereof shall be marked by the keeper of the register on the plan signed as relative to the writ.
Along with each register volume transmitted to the Keeper of the Records for custody there shall be sent the duplicate plans, if any, relative to any of the writs engrossed in such volume.
Such duplicate plans when transmitted to the Keeper of the Records shall remain in his custody, subject to the same rights on the part of the public to have access thereto as apply to the Record Volumes.