Roman Optics?

[galileo-034]

The point is valid, yet assuming the Roman empire would be the same.
A fast communication network of semaphore that puts all provinces of the empire within a day range is something that would revolutionize the very structures of the Roman society and of the empire as we know it (Rome-Eboracum through the Dover straits is 2,400 km or 6 hours, Rome to the Upper Egypt border through Byzantium, Antioch and Alexandria, 5,700 km or 14-15 hours, Rome to Carthage through Liguria, Arelate, Barcino, Toletum and the Pillars of Hercules across to Mauretania, 4,800 km or 10-12 hours).

A governor or a general who is weeks or months away has far more autonomy in decision making than one who is one day away.
If anything, that would enable, and compell further centralization of the Roman empire, and an ever bigger bureaucracy in Rome to handle it all. Economy wise, you can know within the day if a storm has broken out in the Ionian sea and relay the information to a ship about leaving the port of Alexandria. You can conduct long distance transactions for trade, which in turn will incite long distance proto-banking and insurance business.
Of course, the downsides exist. News of a military defeat go faster, be amplified, panic can result...

Two examples of what could change.
The revolt of Avidius Cassius for instance. A semaphore line to the Danube frontier and over to the campaign headquarters of Marcus Aurelius means the rumors of his death get dispelled faster, and Avidius don't revolt.
Of the revolt of the Goths in the 370s leading up to Adrianople. A more centralized government don't allow one man like Lupicinus as much leeway as OTL so he could not extort the Goths and cause their revolt.
Of course, one could spin the events in the other sense, and there are countless events that could go differently.

But before getting to events, I think it might be more useful to examine how much transformed would be the Roman empire and not simply basing on the OTL trends and problems to conclude to the same result, at least not without asking if these problems and cause might or not be affected by the social, cultural, economical and political consequences of a fast communications network.

 

[Flavius Iulius Maiorianus]

You can conduct long distance transactions for trade, which in turn will incite long distance proto-banking and insurance business.

Excellent post, but I just wanted to point out that the Romans definitely had banking, and if I remember correctly they at least had some form of insurance, though I'm not as confident in that.

 

[EasternRomanEmpire]

The point is valid, yet assuming the Roman empire would be the same.
A fast communication network of semaphore that puts all provinces of the empire within a day range is something that would revolutionize the very structures of the Roman society and of the empire as we know it (Rome-Eboracum through the Dover straits is 2,400 km or 6 hours, Rome to the Upper Egypt border through Byzantium, Antioch and Alexandria, 5,700 km or 14-15 hours, Rome to Carthage through Liguria, Arelate, Barcino, Toletum and the Pillars of Hercules across to Mauretania, 4,800 km or 10-12 hours).

A governor or a general who is weeks or months away has far more autonomy in decision making than one who is one day away.
If anything, that would enable, and compell further centralization of the Roman empire, and an ever bigger bureaucracy in Rome to handle it all. Economy wise, you can know within the day if a storm has broken out in the Ionian sea and relay the information to a ship about leaving the port of Alexandria. You can conduct long distance transactions for trade, which in turn will incite long distance proto-banking and insurance business.
Of course, the downsides exist. News of a military defeat go faster, be amplified, panic can result...

Two examples of what could change.
The revolt of Avidius Cassius for instance. A semaphore line to the Danube frontier and over to the campaign headquarters of Marcus Aurelius means the rumors of his death get dispelled faster, and Avidius don't revolt.
Of the revolt of the Goths in the 370s leading up to Adrianople. A more centralized government don't allow one man like Lupicinus as much leeway as OTL so he could not extort the Goths and cause their revolt.
Of course, one could spin the events in the other sense, and there are countless events that could go differently.

But before getting to events, I think it might be more useful to examine how much transformed would be the Roman empire and not simply basing on the OTL trends and problems to conclude to the same result, at least not without asking if these problems and cause might or not be affected by the social, cultural, economical and political consequences of a fast communications network.

That is assuming the Romans do it and it's possible to do it in the way you are imagining it.

 

[Evil Crusader]

The point is valid, yet assuming the Roman empire would be the same.
A fast communication network of semaphore that puts all provinces of the empire within a day range is something that would revolutionize the very structures of the Roman society and of the empire as we know it (Rome-Eboracum through the Dover straits is 2,400 km or 6 hours, Rome to the Upper Egypt border through Byzantium, Antioch and Alexandria, 5,700 km or 14-15 hours, Rome to Carthage through Liguria, Arelate, Barcino, Toletum and the Pillars of Hercules across to Mauretania, 4,800 km or 10-12 hours).

A governor or a general who is weeks or months away has far more autonomy in decision making than one who is one day away.
If anything, that would enable, and compell further centralization of the Roman empire, and an ever bigger bureaucracy in Rome to handle it all. Economy wise, you can know within the day if a storm has broken out in the Ionian sea and relay the information to a ship about leaving the port of Alexandria. You can conduct long distance transactions for trade, which in turn will incite long distance proto-banking and insurance business.
Of course, the downsides exist. News of a military defeat go faster, be amplified, panic can result...

Two examples of what could change.
The revolt of Avidius Cassius for instance. A semaphore line to the Danube frontier and over to the campaign headquarters of Marcus Aurelius means the rumors of his death get dispelled faster, and Avidius don't revolt.
Of the revolt of the Goths in the 370s leading up to Adrianople. A more centralized government don't allow one man like Lupicinus as much leeway as OTL so he could not extort the Goths and cause their revolt.
Of course, one could spin the events in the other sense, and there are countless events that could go differently.

But before getting to events, I think it might be more useful to examine how much transformed would be the Roman empire and not simply basing on the OTL trends and problems to conclude to the same result, at least not without asking if these problems and cause might or not be affected by the social, cultural, economical and political consequences of a fast communications network.

I think this is very much going overboard.
If stations are busy doing government work, they won't be able to do other things, nor can they operate by dark, effectively locking the system down for possibly even 3 days as they wait for a confirmation signal. Parallel stations can be built, but carry significant risks in confusion; plus, all Chappe systems bar the Swedish one were strictly for the center to poll the stations and vice versa, but the stations could not independently talk to each other, and that is with far superior literacy/centralisation/actual civil servants running the system.
So in practice, what we're looking to is a system where the Emperor is very much restricted to the place where the Optic Telegraph lines trend towards (far more likely, some place like Mediolanum), because that is the ultimate necessity of policy making, but troops still need to be fairly close to the actual theaters of operation. Doesn't seem a great recipe, honestly.

 

[Elfwine]

So in practice, what we're looking to is a system where the Emperor is very much restricted to the place where the Optic Telegraph lines trend towards (far more likely, some place like Mediolanum), because that is the ultimate necessity of policy making, but troops still need to be fairly close to the actual theaters of operation. Doesn't seem a great recipe, honestly.

That sounds like it would be handy in a very situational way - which is to say, it might make some differences in some situations that matter, but we're not looking at a "fast communications network" that covers all or most information in the first place (based on your comment on Chappe systems).

 

[Evil Crusader]

That sounds like it would be handy in a very situational way - which is to say, it might make some differences in some situations that matter, but we're not looking at a "fast communications network" that covers all or most information in the first place (based on your comment on Chappe systems).

My point is that the overall velocity of information would be very uneven in impact and not too practical: fast where not as needed, and yet not as able to carry info as we would want to make an impact. The Roman defense system was, much like the roads, a long-term investment: it created natural pathways for invasion that could allow Legions to act as quick response forces even without optic telegraphs. Even accepting the superior estimates, which probably are more correct, those messages aren't gonna change that people have to go places by foot, so saving a few hours over a rider relaying info at best (because especially barbarian raids are not going to try and pass with optimal weather conditions, which also impact optic telegraphs, and in case of attacks, commanders did have authority to repel them with the Legions they were assigned, purposefully, command of) has an unexpectedly small advantage, and of course, the line is only able to handle one communication effort at a time unless we're pushing it, but even then, the info density is only good enough for central government needs so it cannot function as a technological diffusion vector most of the time.

 

[JJ2161]

Just diplomacy and trade wise...

See Rome to Ctesiphon, the capitals of the two biggest rivals... About 4,300 kilometers or ten hours for a Chappe signal.
View attachment 891652

From the Persian capital to the Eastern Han capital of Luoyang, following the Silk Road, another 6,800 kilometers or 14 hours.
View attachment 891654

So, theoretically, a message could reach Rome from the Son of Heaven's court in Luoyang - or the other way around - in 24 hours.
Of course this line would grow by chunk, each managed and built by either Romans, Persians or Chinese, for their own purpose, gradually, with the use of spyglasses spreading, along with the concept of Chappe like semaphores. It would also depend on maintaining presence in relays, and defending those relays, but even if the lines is interrupted on some Central Asian portions, the communication speed between Han China and the Mediterranean world would drop from months or even years long journeys to weeks, and days in the best times.
That would massively boost the volume of information travelling from one end of Eurasia to another, which would in turn further incentivize the use of this Silk Road line of semaphores.

In my alternate history, the capital of the empire would be transferred to ATL Constantinople (called Romanova in this version) in the 150s. That is because Rome would manage to conquer Persia and hold it for a century or two before it gains its independence back. So, I though Byzantium would be a perfect central point to rule an empire that spanned from Portugal to the Indus Valley.

 

[JJ2161]

Such a line would cost a fortune to build, to train all of the qualified personnel and more importantly to maintain, while it is theoretically possible what advantage would the Romans and Chinese gain from this? Spreading Christianity and Confucianism? They can do that by sending missionaries. Also imagine how many mistakes could happen if the translators make a small mistake and the next one makes another one... It would be extremely unreliable

I thought such a system would have more military and administrative than diplomatic use, at least for the Romans. By creating a network that spanned the empire, the government in the capital would have easier and faster communication with the provinces, allowing for greater centralization of power and quicker government action. Militarily, if the news that a barbarian tribe or rival empire is encroaching on Rome's frontier were to reach Rome or Constantinople in days instead of weeks or months, I'd think the Romans would be able to act way quicker.

 

[EasternRomanEmpire]

I thought such a system would have more military and administrative than diplomatic use, at least for the Romans. By creating a network that spanned the empire, the government in the capital would have easier and faster communication with the provinces, allowing for greater centralization of power and quicker government action. Militarily, if the news that a barbarian tribe or rival empire is encroaching on Rome's frontier were to reach Rome or Constantinople in days instead of weeks or months, I'd think the Romans would be able to act way quicker.

Administration has the same problem as diplomacy: it's very unreliable for complicated messages; as for military use, the information may travel faster but the legions won't, so it still has to be in the area to counter the barbaric invasion and it would be a day faster than information on a horse so not much has changed