I have always had a bit of a fascination for horology, I think it started when I was about 8 years old and bought a Rolex watch from a jumble sale. I had no mre idea as to what I had at the time than the person that had donated such a valuable time piece. It wasn't one of the mega dear ones but it was quite nice. Or at least it was until I decided I needed to take it to pieces to see how it worked. It was never quite the same after that, in fact I had destroyed it. I had found it fascinating though and have remained fascinated by clocks and watches ever since. I have a small collection of various watches, nothing particularly exciting and for a while I made a living restoring clocks and selling them on. One clock I could never bring myself to sell on is a Gent's Pul-Syn-Etic master clock. These clocks were often used in schools, factories and large office buildings - you would have one master clock and any number of slave clocks, all telling the same time, all controlled from the master clock.
My secondary school had one, it hung on the wall of the Headmasters office next to the case with the glass front where his cane took pride of place and not far from the locked desk that contained all the confiscated pornography.
I guess it was installed when the school was built back in May of 1960, it was still clunking away every 30 seconds when I was there until 1980. Yes, every 30 seconds the master clock would send a pulse to all the other clocks to tell them to activate a solenoid that would act on a ratchet wheel and advance the clock hands by half a minute.
There were thousands of these devices made back in the day, they were pendulum driven with electrical assistance to keep the pendulum going rather than a clockwork mechanism, some had battery backk upp so they didn't have to be reset after a power cut. You could also get bell systems to work alongside them so that the school or factory bell could be triggered to advise of lunch time or end of day. They were really well made, typically in oak cases with glass doors so you could see the pendulum swinging away at the rate of 1 swing per second.
I have mine installed in the man cave, I did have a few slave clocks, I was going to have one in the cave and one in each of the two workshops but with me being me I never got around to it and once I had got it working I lost the drive needed to finish the job. I might get to it one day but it won't be for a while as I have 4 bikes and the hot rod to get done. I will get to it though, it's a nice thing.