What technological advancements led to the telegraph?

[Umbran]

Other factors to consider include mechanical strength if you want suspended wires (gold is not very strong), corrosion (iron will rust), theft (someone will want those gold wires), manufacturability (the ability to extract aluminum is a _very_ recent innovation), and cost. Silver and copper are probably your best bets. You could also give whatever properties you want to mithral, adamantite, and so on. Mithril as a superconduxtor might be fun.

These are all very good points to keep in mind.

Note that if your coinage and economy are based upon the metals, your cables just aren't going to stay up for long.

Also note that the ability to make a basic circuit, and the ability to make a circuit ten to hundreds of mils long and send a discernable signal through that wire, are not the same thing. Electrical telegraphy also requires a reliable, moderately "clean" (in the signal sense) and rather powerful electrical source. You don't start off running long-distance communications off the equivalent of a nine-volt battery...

 

[Rogue765]

What is generally misunderstood in the development of telegraphic systems is that the electric telegraph was not the original telegraph system.

The first telegraph systems, from which the term "telegraph" is derived, were purely optical systems.

They consisted of towers, with mechanical arms. The arms held coded flags/boards, and were moved in a manner simular to pintaphor. The towers were spaced miles apart within line of sight of each other. The operators used telescopes to see the message that the other tower was sending, and then set their tower to relay the message to the next. In this manner messages could be transmitted much faster then by courier. France had an extensive coast to coast system that predated the invention of the electrical telegarphs by about 100 years. (you should check my facts here, I am quoting a TLC program from memory. I saw the program 2 years ago.)

And the Romans had such a system 1500 years earlier.

An excellent source is James Burke's Connections, a documentary series (and books) that shows the progress of technology leading to many inventions, and shows that the path of invention isn't always as cut and dry as you might think, that many inventions are based on technological as well as socialological changes that in many instances are rather random, such as ancient coinage leading to the printing press.

 

[Aluvial]

Resistivity of materials
metal resistivity,
nano-ohm-meter
silver 14.71
copper 15.80
gold 20.11
aluminum 25.00
zinc 54.55
iron 87.10
lead 193.00
mercury 983.96

Silver is best for conductivity, then copper, gold, and so on. Other metals work too, but the previously mentioned ones are the best conductors, and as you go to less conductive metals the possible range between telegraph stations becomes smaller due to lost power to electrical resistance.

Other factors to consider include mechanical strength if you want suspended wires (gold is not very strong), corrosion (iron will rust), theft (someone will want those gold wires), manufacturability (the ability to extract aluminum is a _very_ recent innovation), and cost. Silver and copper are probably your best bets. You could also give whatever properties you want to mithral, adamantite, and so on. Mithril as a superconduxtor might be fun.

Cost is definitely a factor. Copper wire is definitely the best for the 'common' world, Elves might use silver just to make it fun...

Having worked in a limited capacity for a electrical co-operative designing both above and underground power, I want to add that timbering is an essential part of erecting a telegraph system. Poles to hang the wire are essential for a successful operation. Maintaining those poles and lines is also important. Theft of the copper is also a real possibility. Think of the common serf or peasant working near the poles in question. They will eventually start trying to steal the wire to sell at a later point. Copper is not cheap.

Back to the poles. A common stretch of wire over 100 miles will have many poles. Pole distance is determined by the thickness and tensile strength of the copper being used and by a number of other very important factors. The engineering for the wire would have had to been developed at the same time. Average weather would have to be considered, as well as a system designed for high winds. Most systems in temperate climates are designed to withstand a 1/2 inch of ice and winds up to 45 MPH. With those considerations in mind, and average span today would be every 200 to 400 feet. 200 feet between poles would be a good estimate for the time of an advanced fantasy world. I think a mile is 5,280 feet, so 100 miles would have 2,640 poles. That's a lot of lumber considering that most of this line would have to be at least 15' off the ground. The reason you do that is not only for safety, but for security against theft. Speaking of 15' out of the ground, the average depth of a sunken pole is 3' + 1' per 10' above ground. So consider a 15' pole to be actually 20' long. Pine is typically used for this endeavor because the trunks typically grow straight and fast.

Another consideration would be for maintaing the poles against termites and other boring insects. Poles, even at conception, were treated against rot. The average pole today has an average lifespan of 20 years, but they are aggressively treated. Poles uses to be bored and filled with creosote ( http://www.chemicalexposureresource.com /), a terrible chemical that is extremely carcinogenic. Without wood treatment, meaning an aggesive use of chemistry (which opens up a huge can of worms when considering technological advancements), there would be no telegraph (Alchemy skills or minor magic could make up for this I suppose, Ironwood would be fantastic, although not many Druids would go for ruining the land with such deforestation).

As previously mentioned, mining operations would be a must, and consistency of the wire would have to be considered. I disagree with insulation for the wire however, insulation for wire is a more modern convienece and had a lot to due will the invention of rubber and the vulcanization process (Goodyear, 1837 and 1844). Although rubber was (just) available, it is not a necessity for the process to work. Check out this link about the telegraph... http://inventors.about.com/cs/inventorsalphabet/a/media_2.htm

Another intersting fact is the rapid advancement of the radio after the telegraph. Marconni invented and perfected this right before the turn of the 20th century I think in 1896. http://www.marconiusa.org/marconi/index.html Although there were 60 years of telegraphy, the radio changed the way telegraphy was instituted.

Here is an interesting site about inventions by subject and their invention dates. Remember that even though the item in question was invented at that particular date, widespread acceptance and use was generally 2 to 10 years after the invention in question was created.
http://web.archive.org/web/20031012064709/www.lib.lsu.edu/sci/chem/patent/srs136.html

Hope this helps.

Aluvial

 

[Joshua Randall]

For a fictional account of the building of a small-scale telegraph, read the book The Mysterious Island, by Jules Verne. (An absolutely fantastic book, by the way.)

 

[lukelightning]

Electricity and lightning doesn't work in D&D the same way it works in real life; it's entirely possible that electricity in a fantasy world doesn't have the same magentic effect it has in real life, etc.

I'd personally rule than in a fantasy world, electrical telegraphs do not work; if you want long range communication like this, use a magic item.

 

[BeauNiddle]

If you want a long distance communication service in D&D why not use crystal balls?

A mage creates tuned crystal balls which can only see one location but can be used by anybody. The person who wants to send a message pays a message clerk to put it in the tuned message room which can be seen by a scripter in hub A. The scripter takes a copy of that note and then forwards it from the hub to the destination in much the same way. 2 way crystal ball links require the same set up as a telgraph office (give your message to somebody else to send, people inbetween read it, pass it on, recipient has to pick it up from another office) without having to come up with wires, etc.

Of course if the world already has the tech you might as well go with the telegraph.


On thing I thought a telegraph would require is peace and stability - if people come round regularly pulling down your telegraph poles then the business is never really going to take off. In a land full of monsters how do you protect the telegraph lines?

 

[Andor]

Well it was a GM posting that he wants technological elements in his world, so it seems unlikely he's going to rule out the very elements he wants, eh?

At any rate a telegraph is a very simple device as electronic devices go. The circuit closes, current flows through a wire and generates a magnetic field. A coil in the wire produces a stronger local field and drives a small iron bar to make a clacking noise. This is the same technology as a relay or a solenoid, just applied differently.

All you need to make one is a lot of copper (or silver or gold) and a little iron, and a current source. A volatic stack would work for short distances, a generator for longer ones. Alternating current is vastly more efficient for long distance transmission that direct current. That's why we use it.

Where things get interesting is how all this interacts with magic. Frex, can wizards create a vine that is conductive? (Shambling mounds seem like a good place to start.) Can druids coax this vine to grow from branch to branch along the trees sheltering the kings highway? Will spells intereact with it? Magic mouth for example? Perhaps current is generated by trapping lightning bolts in Leyden jars with enchanted stoppers to let it out slowly.

The pace of modern change came from a great many things interacting, with modern chemistry and cheap steel driving the pack. You can control which of these things happen or are even possible. No bessemer furnaces means no steampunk. Also you might have sociological factors which slow the pace of change. For example perhaps the priests of the god of technology must approve all new devices before they are sold to the public and they have a long application process (Elves you know.)

And let me second the recommedation of Connections. You might find them at your library?

 

[hagor]

What is generally misunderstood in the development of telegraphic systems is that the electric telegraph was not the original telegraph system.

The first telegraph systems, from which the term "telegraph" is derived, were purely optical systems.

They consisted of towers, with mechanical arms. The arms held coded flags/boards, and were moved in a manner simular to pintaphor. The towers were spaced miles apart within line of sight of each other. The operators used telescopes to see the message that the other tower was sending, and then set their tower to relay the message to the next. In this manner messages could be transmitted much faster then by courier. France had an extensive coast to coast system that predated the invention of the electrical telegarphs by about 100 years. (you should check my facts here, I am quoting a TLC program from memory. I saw the program 2 years ago.)

For what it's worth, Terry Prattchet described some sort of (semi-magical?) semaphore system in his more recent Discworld novels. It is referred to as "the Clacks".

more info:

http://en.wikipedia.org/wiki/Clacks_(Discworld)

Hagor

 

[Whimsical]

Animal messenger can be cast by a 3rd level NPC druid for 60 gp, or a 4th level NPC ranger for 20 gp. The range would be as far as the animal can go in three days for the druid, or two days for the ranger. NPCs with good Handle Animal skill can train carrier pidgeons to ferry messages between stations that they have set up. Probably for less than 20 gp per message.

Series of crystal balls would be very cost prohibited for common use.

The key to the telegraph was discoverd by a necromancer when he discovered that whenever he moved a finger on one of his animated skeletons, the same finger on the other hand mimicked its motion, even though the hand was not connected to the skeletal body. He then determined that distance was not a factor for this strange effect after experimenting with several distances and between various barriers. After working to create a simpler spell that just worked on the fingers, he came up with a 0-level cantrip called animate finger which a spellcaster could cast on one of the fingers, move it up and down, and the paired finger would replicate this movement for a short duration even if it was thousands of miles away. This was the birth of the telegraph.

 

[Warbringer]

What metals are good, easily available conductors? I'm thinking of denying my world iron, steel, even bronze maybe. However, an abundance of gold would work out well. So, what metals in particular could work in a telegraph line?

Bronze is an alloy: so, either it didn't happen, or their is no copper, or no tin. No copper takes a way a major semiconductor.

So are you saying, there is no iron at all in your world? or just that players have never found it? If the former, you'll have an alomst purely magical world; no iron, no spinning core, no electro-magnetism, lots of very crisp suntans...

On another note, I love the communication sytem used by the necros in Chronicles of Riddick - undead psychics...

How about its simply a bound elemental in a very long piece of "X"... enter metal of choice.

The elemental is the power source and the solenoid.

Expensive, yep, but so was telegraph when it was first introduced