As all novices know, a drucrafter can’t control any bit of random essentia floating around in the air. They can only control their personal essentia; essentia that has taken on the psychic imprint of their mind and body.
All living creatures have a reserve of personal essentia. Essentia capacity measures this reserve’s effective size.
Personal Essentia
Personal essentia is crucial for two out of the three drucraft disciplines. It allows a drucrafter to channel (by directing their personal essentia into their sigls to activate them) and to shape (by forming the kernels of sigls).
The turnover rate for personal essentia is very high. It is constantly created (as new essentia flows into a creature’s body and assimilates to it) and lost again (as it drifts away and become un-attuned). Since essentia is everywhere, this constant cycling is not usually an issue – a living creature’s personal essentia reserves will continually rise and fall, but this naturally evens itself out, like water finding its own level. This ‘evening out’ process happens constantly, from minute to minute, typically without the person in question ever noticing that anything is happening.
However, all this changes once that personal essentia is spent on something. A normal person can’t possibly deplete their reserves of personal essentia, since they have no way to spend it. A drucrafter, however, can. At this point, their essentia capacity suddenly starts to matter.
The Lorenz Scale
Essentia capacity is measured on the Lorenz scale, named after the drucraft researcher who formalised it. The Lorenz Scale is calibrated to the Lorenz Ceiling, which is the maximum amount of personal essentia input that a sigl can accommodate before its efficiency drops sharply. The Lorenz Ceiling is defined as a 1 on the Lorenz Scale.
Most sigls have a Lorenz rating of 1. Thus, a drucrafter’s Lorenz rating measures how many (ordinary) sigls they can sustainably use at once. Sigls with a Lorenz rating of less than 1 consume proportionately less of a drucrafter’s ‘budget’; sigls with a higher Lorenz rating consume proportionately more.
Reserves and Rates of Change
Although essentia capacity is commonly viewed as a reserve, or a pool, it can be more accurately viewed as a rate of change. It’s not a measurement of how much personal essentia you can hold, it’s a measurement of how quickly you can replenish it. So if you have an essentia capacity of exactly 3, this means that:
- using 1 standard-rated sigl at once is easy;
- using 2 standard-rated sigls at once is easy;
- using 3 standard-rated sigls at once is possible but difficult (you would have to channel very efficiently, and might need to pause to take breaks)
- using 4 or more standard-rated sigls at once is impossible (you would run out of essentia almost immediately).
What Determines Essentia Capacity
Essentia capacity is primarily physiological. It’s a physical trait, like height and weight, and can be measured quite precisely with modern instruments.
While many factors seem to affect essentia capacity to some degree, the strongest correlation is with a person’s skeletal mass: the combined weight of their bones and skeletal muscles. Note that this correlation, while strong, is not one-to-one; there are some rare drucrafters with a high skeletal mass and a low essentia capacity, and vice versa. Total body mass is sometimes used for a quicker estimate, but this produces a less accurate result since fat tissue and parts of the body that are metabolically inactive seem to affect essentia capacity to a much lesser degree.
Average essentia capacity in the United Kingdom is 2.8 for men, and 2.4 for women. These values vary across the world in rough proportion to average height and body size.
Changing Essentia Capacity
Because of how essentia capacity is viewed (see next section), significant efforts have been spent researching ways to increase it.
These attempts have for the most part shown limited success. By far the most effective methods to increase essentia capacity have proven to be drucraft training and strength training. Channelling practice can slightly (but reliably) increase a body’s efficiency in assimilating essentia; physical training and conditioning to increase muscle mass has a similarly positive effect.
These increases, however, are quite small. Such training virtually never produces an increase of over 20% (10% is more normal) and in any case brings diminishing returns. No matter how dedicated, all drucrafters eventually reach the point where they are forced to accept that they have pushed their essentia capacity as high as it’s going to go.
More invasive techniques have been tried, but these tend to come with unwelcome side effects, and as such, their use nowadays is frowned upon; common consensus is that the benefits of trying to force a higher essentia capacity simply aren’t worth the costs. However, given how much value is placed on essentia capacity, there’s always someone willing to take the risk.
So this characterisation makes essentia capacity/use rather akin to breathing – barring an external force or catastrophic physiological error, it’s really unusual and hard to run out of air, and trying to force yourself to, say, not breathe will work until your instincts take over or you pass out and cease exerting the necessary will. Similarly, if you try to channel above your capacity, you’ll “run out” of essentia very quickly, but presumably that just means the sigls will stop working and your natural replenishment will continue.
I’m guessing if you have too much draw from continuous sigls that don’t require manual activation, they’ll work either poorly or intermittently, depending on the sigl, like a light bulb hooked up to too low power, or a muscle soaked in lactic acid (and as such not receiving enough oxygen)?
Pretty much, yes. There are some bad consequences that come from running too low on personal essentia for too long, but that’s a topic for another article (and it’s quite rare for that to happen unless you’re doing it deliberately for some rason).
I presume theres a way to keep a drucrafter personal level lows by external means – to limit their action potential – when holding someone against their will?
And knowing the wickedness of the world this can evolve into torture?
Or is it purely up to the person themselves?
There are some methods, though they’re pretty esoteric and aren’t in common use.
Seems like the easiest way to hold a drucrafter captive would be to just take all their sigls. Barring some primal effects, they wouldn’t be able to actually use their essentia for anything then. (Assuming they didn’t do anything odd like imbed a sigl subcutaneously or swallow it.)
Since we know that essentia can be stored at least temporarily from the draining of wells, is it possible to provide a short term boost of essentia capacity using some sort of storage device.
Clearly this would be for a triggered effect but just thinking that this might be a way to boost an effect for a short period of time. Think of an extra strong push or light.
Yes, there are Primal sigls that do exactly that.
Oh! That sound both interesting and very useful for Stephen!
At the moment I’m still not understanding how essentia gets taken out of wells and stored – perhaps you need an engineer and a machine as per the Tier raid…
It’s pretty much exactly the same as making sigls. Anyone with basic shaping skills can take the essentia from a Well and crystallise it into a piece of aurum. And even if you can’t shape, there are sigls that can do the job instead.
Many thanks for that – Doh! I was thinking it was more complex – somewhat like that Tier specialist used.
Do the Armsmen actually have any drucraft skill or are their protection/attack sigls set on “automatic” and operate unconsciously?
While one can’t change ones personal essentia capacity by very much perhaps skilled drucrafters are able to design sigls that, while doing the same job, have a lower Lorenz rating? I’m thinking, for example about the Slam Sigl, where it could be set on continuous charge-up and only require attention from the drucrafter to activate the stored charge in a fight. Might this lower the Lorenz rating?
Depends on the armsman. New recruits don’t have sigls at all. Higher-ranked ones have continuous sigls that operate automatically. Elite, long-serving armsmen might eventually get tapped for drucraft training and would get active sigls that they could use on their own. This puts quite a lot of power (and wealth) into the hands of the armsman, though, so this is something you only do if you trust the person.
Huh I guess Scar and Diesel were somewhat competent, it seemed kinda of odd that they were with House Ashford… unless Charles knew they weren’t that effective and did it to undermine Lucella seems like something he would do.
Did William, Stephen’s Dad get training and sigls from House Ashford despite his young age? If so I could see why Charles took him marrying his daughter so badly for some reason I got the feeling they saw each other as a surrogate father/son relationship for some reason.
Good spot on your part. Yes, and you’ll find out the details this autumn when Book #3 comes out.
Since essentia capacity is so strongly linked with the mass of the skeleton & skeletal muscle, how much does a person’s essentia change as their skeleton & muscles change?
For example, as we get older, bones become less dense & muscle mass/strength tends to decline. But people can go the other way, too: they can “bulk up” through intense exercise & a high protein diet.
So, is a person’s essentia capacity a constant thing? Or will it gradually decrease as they age? And, if so, can a person stave off that age-related decline in capacity through exercise & calcium supplements? Can they increase it through weight-bearing & muscle building exercises?
Yes, you can (slightly) increase essentia capacity through conditioning and strength training. But it’s usually not as much as people would like, and you eventually hit a point of diminishing returns where you can’t realistically push it any higher.