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April 28, 2011 9:49 AM   Subscribe

I am trying to come up with the "ultimate utility tattoo" and I need some help with what would be on it. You've a full sleeve (an adult male's arm and shoulder) to work with so what important information do you think would be useful?

By "utility" I mean - if this person were dropped naked into the middle of any point of human history they would have access to a whole bunch of information that would prove of use. I've seen a whole bunch of science related tattoos but I'm thinking that the chemical symbol for LSD or caffeine is perhaps not as much use as the maths that describes a cannonball's ballistic arc.

Now to set it straight from the get go it's not going to be implemented as a real-life feature on my arm but since I do have a sleeve partially planned I may nick suggestions that tickle my fancy. This is more something that I intend to use in an RPG setting where a traveller must go unclothed and carrying nothing in a Terminator stylee so this sort of thing would be rather handy. Also - it's (imho) cool.
posted by longbaugh to Science & Nature (38 answers total) 34 users marked this as a favorite
 
Probably as much of this as you can cram in to the design.
posted by wcfields at 9:52 AM on April 28, 2011 [38 favorites]


Identifying marks of as many poisonous insects and reptiles as you can fit.
posted by bonobothegreat at 9:57 AM on April 28, 2011 [1 favorite]


Maxwell's four equations, and then tell people that they can derive what they need from there.
posted by COBRA! at 9:57 AM on April 28, 2011 [3 favorites]


Edible plants for your geographical area!
posted by Greg Nog at 9:58 AM on April 28, 2011 [2 favorites]


How basic are you thinking?
Super basic:
How to light a fire.
How to make a bow (or spear) and arrrowheads.
Basic first aid.

Less basic:
How to make gunpowder.
How to pick a lock.
Human anatomy.
posted by Glinn at 9:58 AM on April 28, 2011


The Pioneer Plaque was meant to express this stuff to aliens, so would that work?
posted by Think_Long at 10:00 AM on April 28, 2011 [1 favorite]


Have a half-ruler in inches tattooed on your forearm.
Have the words "If lost, please return to:_________." And then fill it in with sharpie.
Have Avogadro's number, 6.0221415 × 10^23.
Have the lat and long of your birthplace.
Have your passport number.
Have your blood type and any allergies you might have.
Have the number 42.
posted by pwally at 10:05 AM on April 28, 2011 [5 favorites]


How about a ruler?
posted by me3dia at 10:05 AM on April 28, 2011


More: the Golden Mean, Fibonacci's spiral.
posted by me3dia at 10:07 AM on April 28, 2011


How much of a sleeve would be visually accessible? I'm imagining cricking your neck in the middle of the pleistocene while trying to check the poisonous-plant chart on your shoulder.
posted by L'Estrange Fruit at 10:09 AM on April 28, 2011


The equations for estimating the trajectory of a projectile are simple enough, but the problem is that they involve a lot of trigonometric functions. I guess you could tattoo a bunch of trig tables somewhere, but that would take up a lot of space. Better write down how to do it by hand. The Taylor series definitions will look coolest and can be cranked out by hand given pencil, paper, and time.

Other useful stuff: recipes for explosives, antibiotics, painkillers, and useful metal alloys.

Oh, here's a good one: formulas for calculating the times of solar and lunar eclipses, solstices, and equinoxes. Also, celestial navigation methods.
posted by jedicus at 10:15 AM on April 28, 2011 [3 favorites]


Edible plants? Forget the Latin names, just pictures.
posted by S'Tella Fabula at 10:15 AM on April 28, 2011


Assume the periods being visited are at a level of technology that could be from around 0CE to 1900CE.

How to make gunpowder is easy enough to recall once learned, as is lockpicking. Pictures of plants, insects and things to avoid would realistically take up a lot of space so think text over images given a preference (exceptions will be made for stuff that absolutely requires an image).

wcfields - thank you for that! I'd seen it years ago and totally forgotten what to search for. Since a lot of it is block text I'd say it could be heavily compressed. It also gives suggestions for inventions but not the science behind the inventions which is more what I am after.

Have a half-ruler in inches tattooed on your forearm.

That's actually really very useful and it's a shame there's no equivalent for measuring mass. I'd also already thought of "If lost please return to..." but whilst amusing the person might move address and then what would happen?

You can assume that a mirror or other reflective surface can be used to make the harder to reach areas accessible.

Can anyone smarter than me also tell me whether it would benefit from being in binary format or whether plain English would be better?
posted by longbaugh at 10:17 AM on April 28, 2011


How about the location and dates of the birth of various evil people? You could prevent a lot of bad things from happening.
posted by bondcliff at 10:21 AM on April 28, 2011


it's a shame there's no equivalent for measuring mass

Sure there is: use the rule and a bit of math to create a vessel for a known quantity of water. Given the density (1 kg/L) of water you have mass. From there you can create a simple balance scale.

Speaking of unit conversions, a chart of metric units and their conversion factors might be handy. Introducing the metric system at an early date would be extremely useful.
posted by jedicus at 10:26 AM on April 28, 2011


A ruler won't work to any high level of precision because one's dimensions change with time.

Also, you might enjoy this previous question.
posted by box at 10:31 AM on April 28, 2011


Can anyone smarter than me also tell me whether it would benefit from being in binary format or whether plain English would be better?

One assumes that if this person can remember how to make gunpowder and how to pick locks, they can also remember how to read? It seems much more straightforward to put in in plain English than a format which would require an extra step of know-how to parse.
posted by brainmouse at 10:32 AM on April 28, 2011 [1 favorite]


This is a neat idea, but, realistically, I think there are some flaws to the plan--because the body changes shape slightly, stuff like graphs and diagrams probably can't be to perfect scale (or, at minimum, there's a conflict between legibility and efficient use of space--this conflict also comes up when you start having lines of tiny text). A lot of the information one might include might change subtly, either on the skin or, uh, in the world. And many things which are brief enough to make good tattoo subjects are also brief enough to memorize, especially if you see them on your arm every day of your life.
posted by box at 10:37 AM on April 28, 2011


Also, you might enjoy this previous question.

I was going to mention that. Back then, I mentioned my own idea for having an L and an R tattooed to my forearm.

I've since had this done (left; right). It's not nearly as impressive, nerdy, or obscure as any of the above ideas, but I use it almost daily. I used to have very real and persistent problems following or giving directions, but not anymore.
posted by PhoBWanKenobi at 10:40 AM on April 28, 2011 [4 favorites]


A ruler won't work to any high level of precision because one's dimensions change with time.

If it's a sleeve tattoo then there shouldn't be much distortion along the length of the forearm, which is all that matters for a ruler. Right along the tibia (where the bone is very close to the skin) would be a good low-distortion choice as well, I would think. Ruler marks don't take up much space, especially if you don't bother to number them, so you could do both. Heck, you could mark both arms and both legs for redundancy.
posted by jedicus at 10:44 AM on April 28, 2011


Speaking of sleeves...

Math Cheat Sheet (Shirt)
Science Cheat Sheet (Shirt)
Engineering Cheat Sheet (Shirt)

The Engineering one is probably most applicable.

More: the Golden Mean

I believe that if you have a human body of the usual proportions, you're already carrying this information around with you.
posted by rokusan at 10:49 AM on April 28, 2011 [4 favorites]


If it's a sleeve tattoo then there shouldn't be much distortion along the length of the forearm, which is all that matters for a ruler.

Keep in mind, as I've learned with my forearm tattoos, that a "straight line" is going to be a kind of tricky idea on your forearm because the way the bones/skin rotate with movement. My tattoos are on my forearm if I hold them out in front of me, but if I turn my arm over or lift them up to show other people, it looks like they're on the side of my arm.
posted by PhoBWanKenobi at 10:49 AM on April 28, 2011


How about the location and dates of the birth of various evil people? You could prevent a lot of bad things from happening.

Assume either paradox prevents this or "alternate reality" so no guarantee of same location etc. GM fiat FTW!

One assumes that if this person can remember how to make gunpowder and how to pick locks, they can also remember how to read? It seems much more straightforward to put in in plain English than a format which would require an extra step of know-how to parse.

Purely the concern of limited space. Assume no urgency is required in looking up the specific information and that time is available to extract what is required. Picking locks was a considerably easier thing to learn than equations (well, it is to me anyway).

I think there are some flaws to the plan--because the body changes shape slightly, stuff like graphs and diagrams probably can't be to perfect scale

Crap. I hadn't considered this. What about on a shin or something with a thinner layer of skin next to a bone?
posted by longbaugh at 11:02 AM on April 28, 2011


You're right, jedicus, that some places will distort less than others, but low distortion is not no distortion. And we're talking about a ruler here--accurate and consistent measurements, even at the smallest divisions, are its sole reason for being (hmm--it might be better to focus on scales and tables and ratios and other conversion tools).

(Also, here's a good picture to show what Phoebe is talking about.)
posted by box at 11:05 AM on April 28, 2011 [2 favorites]


How about the Arecibo Message?
posted by carsonb at 11:14 AM on April 28, 2011


Technically speaking, I think a ruler is kinda useless. The only reason to use a particular system of units is so everyone agrees on the system for ease of communication. If inches didn't exist yet, then nobody's going to be using them. If they were in use, then rulers should be fairly easy to find. Otherwise, just use ad-hoc references for measuring needs, which work great. If you need to communicate a length to someone else without an existing standard, it's probably easier to start a standard that isn't based on your arm.
posted by RikiTikiTavi at 11:24 AM on April 28, 2011 [1 favorite]


I'd also already thought of "If lost please return to..." but whilst amusing the person might move address and then what would happen?

How frequently is the tattooed time traveler going to be going back? Also, in what areas will he/she be traveling?

I ask because, if the traveler was focusing on Europe, a message to have their body (or some portion of their body) delivered to the Catholic Church in Rome in return for a reward (that had been previously arranged for at the Church by the traveler and is periodically checked). Upon receipt, the Church then records the date and circumstances, which the traveler then can access in the "now."

With a little forethought (and laser tattoo removal), the drop off point can be customized for every mission. Heck, part of training low level agents could be them going back in time to check the dropoff zones where they could leave little caches of supplies for their final time travelers. These caches could be indicated by ads in newspapers, messages carved on a cave wall, Beatles songs played in the 1700s, etc.
posted by robocop is bleeding at 11:30 AM on April 28, 2011


Methods for isolating penicillin and making gunpowder and steel.

There are direct and practical ideas: Wash hands before doing surgery. Don't shit in the water supply. If someone has these pockmarks on their face then (a) they are going to die and (b) you will too if you don't stay the hell away. Limes should be taken on long sailing trips.

These make no attempt to explain why, but they are simple, easy to understand rules and they work really well.

Then you have the more abstract and philosophical ones: The universe (which includes the earth, the planets, the stars, and humans) follows understandable laws and the best way to find these laws is by observation, hypothesis, and experimentation. There are many scales to the universe, some smaller than we can see and some larger than we can easily imagine.

These are incredibly important, but it takes a long time and lots of people before you can see their value.

Then you have the middle ground: Diseases are caused by microbes.

I actually think this is the least useful. Dropping this information on someone doesn't give them any understanding of where it came from or how to get other bits of information of a similar form and it doesn't directly have any practical benefits.

I say, either go for the big, abstract ideas (if you want to create a grand new scientific civilization) or the low level, practical stuff (if you want to survive through the next week).
posted by It's Never Lurgi at 11:40 AM on April 28, 2011 [1 favorite]


If we can travel through time then perhaps we can program the cells producing hair and fingernails to introduce a colorless (or off-color) segment after X number of metabolic units. The person can then use one of their hairs as a very fine means of calculating length.
posted by itstheclamsname at 12:17 PM on April 28, 2011


I'd also already thought of "If lost please return to..." but whilst amusing the person might move address and then what would happen?

Y'all missed the plot on:

Have the words "If lost, please return to:_________." And then fill it in with sharpie.


The tattoo is permanent. The sharpie writing isn't. The sharpie writing will wear off in days/weeks, so a new person/place can be written in periodically.
posted by de void at 12:25 PM on April 28, 2011


Integration tables. Beautiful, eminently useful, and you'll never be able to take a calculus test again without cheating.
posted by chairface at 12:52 PM on April 28, 2011


You mentioned writing it in binary. I'm pretty sure this would take up more space than writing in English. I don't know how you would encode the letter 'A' in binary such that it would take up less space than just writing the letter 'A'.
posted by SeeTheTurtle at 1:15 PM on April 28, 2011


I don't know how you would encode the letter 'A' in binary such that it would take up less space than just writing the letter 'A'.

A "1" and a "0" can be written much smaller than latin letters and remain legible. You could choose to represent it as a 1 = vertical or 0 = horizontal line. I don't think it would be particularly efficient but it was only a thought :)

There are direct and practical ideas: Wash hands before doing surgery. Don't shit in the water supply. If someone has these pockmarks on their face then (a) they are going to die and (b) you will too if you don't stay the hell away. Limes should be taken on long sailing trips.

These are things that most reasonably well-educated 1st world 21st century folk might know. I agree these aren't needed and that our theoretical time traveller would

Then you have the more abstract and philosophical ones: The universe (which includes the earth, the planets, the stars, and humans) follows understandable laws and the best way to find these laws is by observation, hypothesis, and experimentation. There are many scales to the universe, some smaller than we can see and some larger than we can easily imagine.

This is the really important stuff that I'm after. It's kind of like a cheat sheet for creating a society capable of scientific thought and advances in the quickest possible time. It's easier to perform those experiments when you have already developed the mechanisms by which you can measure the outcomes.

Then you have the middle ground: Diseases are caused by microbes.

I actually think this is the least useful. Dropping this information on someone doesn't give them any understanding of where it came from or how to get other bits of information of a similar form and it doesn't directly have any practical benefits.


Knowing about microbes isn't useful but coupled with the second category you can perhaps create optics that allow you to see them and from that develop further advances in hygiene and health.
posted by longbaugh at 1:52 PM on April 28, 2011


create optics that allow you to see them and from that develop further advances in hygiene and health

You want the Lensmaker's Equation. You'll also need to know how to calculate the refractive index of a material.
posted by jedicus at 2:01 PM on April 28, 2011 [1 favorite]


You can assume that a mirror or other reflective surface can be used to make the harder to reach areas accessible.

Don't forget those parts should be tattooed backwards. :)
posted by torticat at 8:36 PM on April 28, 2011


A table of logarithms plus equations for working out other tables. You could probably set up a neat little business selling maths tables any time from the Renaissance onwards.
posted by Joe in Australia at 9:40 PM on April 28, 2011


Nthing instructions for optics. If instructions for making decent magnifying lenses are writ large, the rest of the tattoo can be in miniscule print. Check out the Long Now's Rosetta Disc for some interesting graphical ideas - they're focused on having a large vocabulary in every language on the disc.
posted by benzenedream at 11:16 PM on April 28, 2011 [1 favorite]


Don't forget a list of historical things to gamble on so your traveler can be wealthy whenever they are. Sporting events, big stock market events, eclipses.
posted by CathyG at 6:29 PM on April 29, 2011


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