Synchronome Electric Slave Clock

I got this old 1930s slave clock from historic Archerfield Aerodrome in Brisbane from a fellow who worked in the hangars as an electrical engineer in the seventies and eighties.
My late Father was a member of the aero club and loved to fly light aircraft.
I remember as a child seeing the big clock in the main building where Dad used to make a flight plan before he took us up for a flight. That was the master clock which would've electrically impulsed all the slave clocks on the aerodrome to keep accurate time.I love this clock and I'm looking at it on my wall right now!
The first and third photo were taken 12 seconds apart!!!