[Filing certified copy of document when original is in danger

of damage or destruction.] Whenever any map, plat or other document on file with or in the official custody of any county clerk in this state shall be in danger of damage or destruction by reason of age, mutilation or any other cause, it shall be lawful for the board of county commissioners of such county to authorize the county clerk to have a true and correct copy thereof made and filed in the office of said county clerk, after having been certified by such county clerk to be a true, correct and compared copy of the original.