Wouldn't this setup actually work though? At least if it's a proper sundial cannon.
Most components of that system are mechanical clocks, which do keep the time on their own, they just drift. The only exception is the gunner who fully relies on an external time signal.
So if that were all, the system would work for a while, but slowly drift and become ever more inaccurate, until it basically has nothing do do with the actual time anymore.
However, the gunner does not always operate the cannon: He only does on cloudy days. On sunny days, the cannon operates itself, using the time signal of the actual sun - which is then passed through the chain and let's the mechanical clocks resync to "sun time".
So in effect, the system's time signal comes from the sun. The rest is just an overly complicated way to "interpolate" the time if the sun is not visible or not at noon.
(Now I also wonder if someone ever build a "self-syncing" mechanical clock - e.g. for a clocktower - using this principle: Use a standard clockwork, but add some mechanism that resets the clock to noon when a focused beam of sunlight hits a certain point.)
The first line says that the gunner operates the cannon every day at noon
> However, the gunner does not always operate the cannon: He only does on cloudy days. On sunny days, the cannon operates itself, using the time signal of the actual sun
That's why I don't understand how you came to this conclusion, what's your thinking behind it?
You're right. The OP article contains a line, that they fire the sundial cannon manually as a "fallback":
> The 6-pound cannon is fired everyday at 1 PM, from May to September. On sunny days the sun automatically sets it to light, but on days when clouds obscure the sun, the sun gunner on duty fires the midday salute with a match.
I imagine that was what reminded the GP of the joke and I kinda used it as context - but yeah, on rereading, it's not part of the joke. I admit, I jumped to conclusions there.
Wouldn't this setup actually work though? At least if it's a proper sundial cannon.
Most components of that system are mechanical clocks, which do keep the time on their own, they just drift. The only exception is the gunner who fully relies on an external time signal.
So if that were all, the system would work for a while, but slowly drift and become ever more inaccurate, until it basically has nothing do do with the actual time anymore.
However, the gunner does not always operate the cannon: He only does on cloudy days. On sunny days, the cannon operates itself, using the time signal of the actual sun - which is then passed through the chain and let's the mechanical clocks resync to "sun time".
So in effect, the system's time signal comes from the sun. The rest is just an overly complicated way to "interpolate" the time if the sun is not visible or not at noon.
(Now I also wonder if someone ever build a "self-syncing" mechanical clock - e.g. for a clocktower - using this principle: Use a standard clockwork, but add some mechanism that resets the clock to noon when a focused beam of sunlight hits a certain point.)