In the English Mechanic and World of Science - Volume 3 - Page 556 from 1866 you will find the advertisement below.
In my humble opinion you have a piece of history beneath your feet, something more than a mechanism to control a door, the longevity of which it does so is astounding (as highlighted in previous posts), is of historical importance, should be a source of National pride (along with others) and we should therefore be doing the utmost to restore, protect and ensure its continued use not only as a method of door control but for future generations to wonder over.