When you say fuse, I assume you mean circuit breaker. Since you say
it looks like four breakers wired together, could it be two double
pole breakers with a common trip? That would be one double pole for
the A/C and one double pole for the dryer circuit. What are the
markings on the ends of each of these four breakers?

Boy, I've learned a LOT from you guys!
It's exciting to find out so much about things I just took for granted.
Thanks!

You are correct.
What I *thought* was four breakers wired together, *appears* to actually
be two sets of two breakers (one I can read is labelled "TYPE BRD,
2 pole unit J1076, BR3030").

It appears that one set of two breakers handles the dryer circuit.
The other set of two breakers appears to handle the outdoor A/C unit.
All four are wired together with a copper wire through the handles.

Why would they be wired together?

All I know is I seriously doubt the house is not to code as it was
just recently purchased and the inspector & lawyers gave the previous
owners about 5 pages of stuff to do. The electricians had to remove
all the wiring in the garage for example, (bummer, the previous owner
had lights all over, now the garage is dark) and they had to install
that copper wire (making it currently impossible to remove the main
circuit breaker panel covering plate without either cutting the
plate metal between the two middle breakers or snipping the copper
wire looped through all the four breakers).

Why would they have a common trip wire?

Does that play a role in hooking up a 230V x,y plus safety ground
compressor temporarily to the dryer x,y plus neutral-tied-to-ground
at-the-breaker circuit?

MM
P.S. Thanks for all the wonderful help. You guys are great!