The most important source of power on Talamh is not as you would expect.
It is neither magic nor wind nor horse.
It is the power of the Tides.
The peoples of Talamh have long since developed the ability to harness the power of their planet's fifty foot tides.
The leading power in tidal power technology is Bigany City. The gigantic port depends heavily on the tidal power to load and unload trade goods from fleets of merchant ships, into thousands of warehouses. It also uses stored tidal power to run the city's defensive siege engines.
Tidal power is measured in tons. This refers to the weight of water stored in cisterns or to the weight of the iron and stone counterweights locked into place within the cities tidal towers.
Many tidal engineers will also refer to distance, being the number of feet that a counterweight can move an object in a given pully system.
Bigany Tidal Power
Tidal Inflow Waterwheel Transmission Mechanism
Bigany Tidal Engineers Guild Note:
(by Gimble Eightfingers)
Before I get into this, I would just like to point out that Eightfingers ain't my damn real name. At least it used not to be. And I don't want to talk about it.
Ok if you must know read the entry on counterweights.
Anyway this is how these babies work.
Actually it's pretty smart, when you think about it.
1. The Tide rises (50' or more per night).
2. Water falls into the holding chamber and turns the waterwheel.
3. The wheel drives the pully.
4. Buckets are dipped and filled with water.
5. Buckets are pulled up the chain.
6. Buckets empty into the Storage Cistern.
7. They travel back down to the waterline.
8. Several tons of power (TPTs - Tidal Power Tons) are stored.
The bigger versions of this can be used to provide more than a thousand tidal power units (TPKs) but they are most commonly used to get good distance (TPD) as they can reach above the tidal levels.
They are very expensive and not very efficient in TPK terms. But the tower they use look pretty cool. So that's something.
Bigany Tidal Power
Pressure Equalisation Valve
Bigany Tidal Engineers Guild Note:
(by Gimble Eightfingers)
This is an inocuous looking and simple piece of engineering. For Uisce's sake, do NOT get this one wrong! If a storage tower or a resevoir cistern blows, the watery explosion will be of such tremendous power that it will destroy the entire dock area and kill thousands.
You HAVE been WARNED!
Bigany Tidal Power
Storage Cistern
Bigany Tidal Engineers Guild Note:
(by Fredgar Plains)
(Gimble Eightfingers is in the Croí infirmary at the time of writing. Apologies.)
While water can be stored in the Storage Cistern by various mechanisms such as an Inflow waterwheel. These mechanisms are expensive to construct and maintain. So they are used to provide power with high TPD (Tidal Power Distance) but lower TPT (Tidal Power Tonnage).
Cistern Storage is cheaper to maintain and construct as it uses a simpler method.
It works as follows:
1. The Tide rises and the Cistern fills (Keep the Pressure Equalisation Valve open)
2. The Cistern doors are sealed at high tide (shut the valve).
3. When the power is required, the valve is released and the doors are opened.
This provides low TPD (Tidal Power Distance) but massive TPK (Tidal Power Tonnage measure in 1000 units).
Bigany Tidal Power
Weight Floatation Mechanism
Bigany Tidal Engineers Guild Note:
(by Gimble Eightfingers)
This one is easy lads.
1. Tide comes in and a massive wooden raft lifts a weight
2. The weight is held in place by ratchets when the tide goes out
3. Release the ratchets to get all that those lovely TPTs
This baby's got decent TPD and can be built big enough to get nearly a full TPK per tower.
Cheaper than a waterwheel but lower on the TPD.
I love 'em though. I could drop ratchet TPTs all day long. "Ratchet Away!!"
Bigany Tidal Power
Cistern Release Counterweight Mechanism
Bigany Tidal Engineers Guild Note:
(by Gimble Eightfingers)
Ah! Now these fellas are a real sneaky piece of work. Invented by Chief Engineer Hepsibah Torc over fifty years ago, Bás rest him, and still to be beat. One of the best guarded secrets of the Guild this one. Hard to build, hard to maintain and almost impossible to run right if you don't know what you're about.
Some say that he cut a deal with the Church and the Clerics of Uisce. Others say he cut a deal with the clerics of Fileadh too. Why they want to be playing with the water levels in the sewers is anybody's guess.
Either way these babies are great if you can get them to work using the special tricks that only the guild knows, and we ain't talking (on pain of death! I'm not kidding...)
So you got your Cistern with all those TPKs and you got a tower with all those huge TPDs. Yeah obvious right? But here's the beauty, this puppy combines the two. Big TPDs and multiple TPKs. Sweet.
All you got to do is time all the valves, ratchets, doors and pullys with an eight man team. Doors open, water flows, pullys whirr.
The drop weight pulmmets under the water weight and the counter rises and is caught by the ratchets.
Sounds simple doesn't it. It ain't. And it shouldn't work. But it does, thanks to old Hepsibah, Croí bless him.
See the diagram? See those three little circles? Yeah? Can't tell you what they do. Sorry but you need to be a 10th tower engineer of the guild for that sort of info.
One last thing I can tell you: She's a dangerous beast. They don't call her the 'contrary weight' for nothing. I tried to pull off a 'Tide' on one of these bad girls with a four man team. Lost two fingers in the process. Lucky I didn't loose half the city too. Stupid Equalisation Valve.
Bigany Tidal Power
Drop Pully
Bigany Engineers Guild Note:
(By Gimble Eight Fingers)
Right Then: Drop Pullys
These are straightforward and are used all over the world. Even Torland know how to build these.
You've got a tower with TPTs and reasonable TPD using counterweight floatation - stay with me.
You just cannect a tripod pully at a perpendicular junction to convert the TPTs to horizontal and hey presto, you've got full motion.
Well I suppose it's not all that easy. The diagram explains it all numbskull.
Anyhoo, this can be used to pull open doors, push heavy objects (using counter motion pullys) and to punch massive holes in things (people, ships, adamantite doors - you name it).
The thieves guild love these babies. They're always trying to persuade decent engineers to 'harness' these to protect their lairs. They're not the only ones. The sewers must be a dangerous place, given the amount of 'freelance' guild work that is available.