Actually the length of a rope is definable. It's the combined lengths of the fibers used to weave it. On the extreme end, if you separate the molecules that make up the rope and attach them in the way that will minimally qualify as a rope, the length of that structure is the length of the rope.
What is a rope? A strand of flexible material that is contiguous (no gaps). Minimally a rope is a series of molecules that each touch exactly two other molecules. If it has gaps it's more properly a chain or a series of ropes. If it's not flexible it's a cable.
Because those molecules will shift around, unless you're at absolute zero temperature, your rope needs to be better-bound than molecules touching if you want it to remain a rope for any length of time. A stable rope is one that can be manipulated in its environment without degrading into a sub-rope structure(s).
A rope does not need to support its own weight. It's quite easy to make a rope that weighs enough to make it snap near the load-bearing end when held vertical.
In DF, the main use of a rope seems to be to tie down a creature. But the amoutn of rope used to tie the knot to the floor (??) and to the creature are identical regardless of the creature. Thus it takes the same amount of rope to tie up a puppy as it does to tie up a dragon - creatures of vastly different neck diameters.
And in a well one rope appears to be able to stretch to an arbitrarily long distance under only its own weight and the weight of a (possibly heavily-decorated) bucket of water. This suggests that DF ropes are elastic. The only limitation is that a rope's volume cannot possibly be larger than the largest single-tile creature. A size 20 creature was shown in the Question of Scale thread to 13,600 kg and the average density of a whale can be described charitably as somewhat close to that of plant fibers like hemp. So the rope is at most 30,000 pounds or so.
In D&D 2nd edition 50' of hemp rope weighs 8 pounds. So you could get 3,750 lengths of rope, or 187,500 feet of rope, in one tile. But that assumes the rope is able to hold its own weight, which 8 pounds per 50' rope will not be able to at that length. If we make the grossly wild assumption that 8 pound rope can hold 300 pounds safely (a big armored human) and another horrible assumption that rope gets to cube its capacity when it squares its thickness (the ratio commonly used is 8x weight for a creature of 2x height), we might be able to work through this.
Note that the volume of rope is expressed in weight here as 30,000 pounds. If we make the rope thicker it automatically loses length in equal proportion. We need to balance it so the rope is able to support its own weight plus the weight of a bucket with water, but not support any additional weight. That will be the longest possible rope.
We need to multiply the capacity of the rope by 100, plus 8 pounds for a gallon of water and the flimsy bucket, which is roughly 4.8 cubed. That means we multiply thickness by 4.8 squared. If the rope is (I assume, again) an inch thick for 50' 8 pound rope, our self-supporting rope is now 23.04 inches thick, nearly two feet. The length of the rope is divded by 23, giving us 8,152 feet. That is the maximum length of DF rope given the above assumptions.
Now one might argue that rope reed or pig tail is stronger or weaker per pound than real-world hemp. That would throw the calculations off dramatically.
And now how long is a tile? I personally think a tile is a 7-foot cube. Dwarves start drowning in water more than 4/7 deep and refuse to path through water 4/7 deep. This suggests that they are about 4 feet tall. It makes sense to divide the liquid levels into familiar units. Of course Toady apparently uses Celcius and so might be said to use metric linear measurements, but unless a tile is 7 meters high I just don't see it as a reasonable way to measure the cube.
7 feet also means humans and elves have plenty of head room. Dragons and colossi are, simply put, either 7' tall or the tile represents the center of the creature and it has limbs that stick out. Size 20 creatures that are 40 feet long should take up 6 tiles x 2 tiles or something, and will probably when Toady implements multi-tile creatures.
If you accept this (and I really could care less either way because you can take the measurements above and do your own thing at this point), the rope can be 1,164 tiles long. There is too much rope to tie around the bucket and the well, so it's more likely that the rope is unwoven and rewoven around the well bracket and the bucket, so no extra length is used up there.
If someone embarks on a site with height greater than 1,164 and creates an active well, or gets a dry well at a lower height, I will go over the numbers again.
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Topic: How Deep can my Wells Be? (Read 6447 times)