Sometimes we talk about how society is "path dependent": what things
would be different if history had not followed its particular path?
One place that's fun to think about is time. Until the
places used local solar time. Washington DC is at 77°W while NYC
is at 74°, so clocks in NYC would be set ~12min ahead of those in
Initially, this didn't matter: traveling from NYC to DC was a multi
day endeavor, so a 12 minute difference in clocks was trivial. As
roads got better and then railroads were built, however, travel times
Atlas of the Historical Geography of the United States, 1932
If you're running a railway system, it's really very useful to choose
a single location's time to use internally. Your workers are moving
East and West, fast enough for this sort of discrepancy to become a
problem, and they certainly don't want to be continuously changing
their watches as they move from town to town. Railway schedules are
much easier to work with if they use railway time, people start using
railway time in their regular life, the government adopts a system of
Imagine, however, that things had gone differently and we were still
on local solar time. At this point it would not be hard to make our
phones always report the correct time as we move east and west, since
our phones know where we are. Automated calendar software could deal
with local solar time with about as much effort as it could with time
zones. Do all routes to the present pass through a system of time
zones, or is there an alternative history where we really could be on
local solar time today?
Railroads need shared time much more than other forms of
transportation. There are a small number of high-capacity tracks, and
the same with vehicles. Efficient use requires central organization,
coordinated operation, and shared scheduling, which is far easier with
a shared time system. If instead of railroads we had developed cars,
it would still be annoying to need to reset your watch as you move
between places, but it would be much less of an issue. Perhaps we
could have had political systems which made private railways
impractical, combined with governments that were not competent enough
to run their own? Or progress in making lighter engines could have
been much faster?
Alternatively, if you had lots of North-South rivers or a society
distributed among islands in an archipelago, railroads would not be
practical and boats are much slower. Perhaps you could have the the
development of computers before the speedy East-West travel that
pushes for time zones?
The telegraph is also an interesting case, since it allows rapid
communication over long distances, if not travel. I don't think the
telegraph or even the telephone provide enough impetus to move society
to switch to time zones. It's just not much of a problem if the
telegraph operator in NYC thinks it's noon when the operator in DC
thinks it's still 11:48. You could have big tables showing the offset
of every city, and allowing quick time calculations when necessary.
With radio and television people do care
about what time different things are going to be broadcast. On the
other hand, they are naturally
the Geography of FM Radio, Erin Davis
This is probably enough to expand local time from being immediately
local to being maybe a ~40mi radius, but that is only about a 2min
time difference. On the other hand, an overlapping chain of broadcast
areas would have pressure to all use the same scheduling time, and at
least in continuously built-up areas like the Northeast United States
that would probably be enough to pull everyone onto the same time.
While the time zone system gives awkward discontinuities, where time
can jump a whole hour in a single step, at this point I would not
seriously push for us to move to local solar time. Still, it's fun to
imagine histories that would have left us with that system.
I can easily imagine a world where the railways switched from local solar time to universal time, without developing timezones. Afterall, the problem with local solar time is that it changes between cities, and that's true with timezones as well, it's just less frequent (and with even hour or half-hour multiples). If anything, universal time would be easier. Universal time doesn't work for non-railroads very well though, so I can totally imagine local solar time sticking around without having to seriously change anything about the world.
The main objection in the link seems to be a pre-supposition that solar time information about different places would be less available than time zone conversion now. That seems probably false. Also, sleep schedules depending on culture and not necessarily lining up with solar time is not any less of an issue now.
It seems likely to me that if we were currently on solar time, there would be a big push for time zones from businesses trying to schedule phone or video call meetings.
Why? If I'm using Google calendar or something, it can show me everything in my own local time and it can show me the different attendees working hours and prior commitments, just as it does today.
This is interesting, because people whose jobs revolve around meeting participation (e.g. corporate executives) would probably still want some sort of scheduling conventions to help them maximize their time available for meetings. If event organizers in different locations were still inclined to choose standard-length meetings, and you still have people who where to maximize the number of meetings in their day, then you have pressure for some sort of non-local scheduling alignment standard (but not necessarily timezones).