Rare serene watch in working order. 1925

Rare sereno or round clock in perfect working condition from the first third of the 20th century. This type of watch was used to control that the watchman or guard made the route that corresponded to them and at the time that corresponded to them, without being able to "escaquear".The case is made of brass, heavy, solid, resistant and very well preserved. On the side of the clock there are two keyholes. One of them is for locking the watch. I do not have that key, although a copy can be made, although as you can see it is open. The clock was delivered locked to the watchman or to the person who made the rounds, so that it could not be manipulated.The idea is simple but very effective. The clock was wound up (more or less charge 30 - 40 hours), and a paper time disc was inserted inside, similar to the one used by the carriers, only this one measured the time, not the speed. A key was inserted in the other keyhole, which made a mark on the paper when it was turned. The marks were different depending on the keys. The keys were located in different rooms or places through which the watchman or watchman had to pass.The watch was hung up, and a record was made in each of these places, so that the paper recorded where and at what time it had been, according to the record left by each key on the disk. At the end of the round, the paper disk was handed to the boss, and then it was time to go home.And one last curiosity. To prevent the interested party from tampering with the disc (opening the clock and setting the time back or forward) there is a blade that cuts the paper every time the lid is opened (it is on the lid) so that you could see if the clock had been opened.I would be happy to answer any questions.