Ok, so I'm stuck on a small pacific island due to bad sailing skills. I've lost everything I had except my laptop and internet connection. Now, my mouth requests water, but movies told me not to drink from the sea. Fortunately, I've found some hidden rum on the island. Should I drink it to stay alive until my laptop battery die (it's a T450s and I have lots of swappable batteries for days), or should I find another way to keep myself hydrated? The rum is starting to be very appealing.


It's been more than half an hour since my last last message. I was perfectly hydrated when I crashed on this island. But now I couldn't handle myself and I started to drink the rum, there is alot of it actually. How much time do I have left? I can stop anytime if I'm told it's bad for me. I've read a teaspoon of salt water every 20 minutes is ok, but I don't have a teaspoon.

[New EDIT]

I'm feeling sleepy right now under the Pacific night sky. Will go to bed (i.e. sand hole) soon. The island is small, no snakes and no coconuts. Bad thoughts crossed my dehydrated mind. If I want to end it all, should I just drink all the rum and hope to pass away without much pain? Anyway, thanks for the answers, I'm going to try them and see if I get any success.

[New new EDIT]

Just woke up, feeling dizzy (shouldn't have drank that rum, or is it the sun + lack of water?). Anyway, my favorite pizzeria won't deliver to my current location. The delivery guy doesn't have his boat/plane/helicopter license, but he is working on it. It's now day 2... Gonna work on the distillery and spend the rest of the day trying to catch some fishes (or is it more smart to stay away from the sun to maximize my survival chances?).


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closed as off-topic by bilbo_pingouin, Magic-Mouse, Green, Frostfyre, JDSweetBeat Sep 21 '15 at 12:57

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    $\begingroup$ Your best bet is wifi positioning your location meanwhile dug a hole drench it with rum don't waste it all light it up by playing with laptop battery and then boil a bottle of sea water use the display of laptop to condensate water vapor. (Without fire process is extremely slow) now you got email, smoke signal, warmth, water, light and rum.🍻 $\endgroup$ – user6760 Sep 21 '15 at 4:37
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    $\begingroup$ Thanks for the help. I should probably stop my paranoia and allow localization in my PC settings, maybe with more rum it will help. Yea, I'm playing with my batteries right now, but good tutorials are hard to find. $\endgroup$ – varnaud Sep 21 '15 at 4:46
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    $\begingroup$ Plot Twist: This is a real-life scenario, not a story. $\endgroup$ – Kaz Wolfe Sep 21 '15 at 8:37
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    $\begingroup$ Order some Pizza $\endgroup$ – PyRulez Sep 21 '15 at 9:00
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    $\begingroup$ If you do fall asleep, make sure your companion doesn't light a signal fire with all the rum. $\endgroup$ – Adam Davis Sep 21 '15 at 12:07

Drinking rum to stave off dehydration is an exercise fraught with hazards. Rum ranges from 40% to 80% alcohol by volume.

Alcohol consumption has been shown to cause dehydration by suppressing production of the Anti-Diuretic Hormone, which leads to increased urination. Excessive alcohol consumption can also lead to vomiting, which is likewise contraindicated when attempting to maintain bodily hydration. The higher quality the rum (i.e. the higher the percentage of alcohol), the greater the dehydration.

Drinking seawater - in any quantity - is similarly contraindicated, as seawater contains more concentrated electrolytes than human kidneys can produce, therefore drinking seawater in any quantity will rob the body of water as the kidneys must use more water than was gained from drinking the seawater in order to flush out the excess electrolytes.

Given that bottles are available, it may be possible to use them as a crude distillation apparatus, using the rum as a heat source ignited by sparks from a laptop battery to vaporise seawater, which can then be condensed in empty bottles. The cool cave in which they are stored may serve to assist condensation of the distilled water.

Of course, there may be other flammable substances on the island, in which case it might be better to burn those, and use the rum as a firelighter.

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    $\begingroup$ Googling "how to start a fire with a laptop battery" right now, thanks. I can spare a few batteries for few more hour of life. Yes, the rum is inside glass bottles, and it seems to have a pretty high percentage (I choked a little). So the trick is to empty them (not by drinking?), fill them with seawater and heat them for water to evaporate into other bottles? $\endgroup$ – varnaud Sep 21 '15 at 4:40
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    $\begingroup$ If the bottles are reflective, you could smash one up and try to use a concave part to focus the sun's rays to start the fire. $\endgroup$ – Peter Sep 21 '15 at 5:25
  • $\begingroup$ @Peter better: a round bottle - if clear - could be used to focus the light when filled with water. $\endgroup$ – Chris H Sep 21 '15 at 9:05
  • $\begingroup$ @ChrisH, alas, the bottles are opaque. $\endgroup$ – Peter Sep 21 '15 at 9:14

Just to expand on the desalination idea already mentioned. What you need is two bottles: one with sea water, and one empty. You then slowly heat the one with the sea water and let it condense back in the other one. Note that a little saltiness is actually good, so it doesn't have to work perfectly.

From what I can tell, the main problem is that you don't have any kind of tube to connect the two bottles. Assuming the bottles are the old-fashioned type, with a large round body, and a small opening, I would recommend connecting the bottles directly, rim to rim, and laying them on their sides. make sure you fill the sea-water bottle about 30%, so that it doesn't spill into the other bottle when you lay them on their sides.

You probably don't even need a fire. Just let the sunlight evaporate the water, bring the bottles into the cave, and put it the right way up (sea water bottle on top. After evaporation, most of the salt should be caked to the surface of the top bottle.

How to connect the bottles? You'll need some kind of gooey substance to make a tight seal. You can then tear strips from your clothing to wrap around the goo, and to wrap around the two bottles to press them together. As for the goo, your best bet is to find a tree and strip its bark in hopes of resin. You could also melt some of the plastic of your laptop case (unless it's aluminium).

  • $\begingroup$ Thanks for the details. How much water can I expect to make using this technique? And to recover the water, do I just unseal the bottles? I would then have to remelt the plastic (if I don't have any resin, gonna check for that). $\endgroup$ – varnaud Sep 21 '15 at 5:30
  • $\begingroup$ About 30% of the volume of one bottle, give or take. You should be able to survive on half a liter a day. Remelting the plastic should work, but I guess that's the thing that's going to run out the fastest. $\endgroup$ – Peter Sep 21 '15 at 5:36
  • $\begingroup$ Solar distillation as proposed won't work. A rum bottle of, say, 10 cm dia by 25 cm long, can only intercept enough sunlight to evaporate about 26 ml/hr, assuming perfect absorption of sunlight and no radiation or convection from the heated bottle. At a guess, you'd be lucky to get 10 ml/hr, and something like 100 ml/day. Or less. $\endgroup$ – WhatRoughBeast Sep 21 '15 at 14:14
  • $\begingroup$ @WhatRoughBeast If he gets 100 ml per unit per day, he basically has 24 hours to make 5 units, and he has his daily minimum. I think that once you get the hang of it, you could easily manage much more units. It's a hassle, but it's doable. $\endgroup$ – Peter Sep 21 '15 at 16:03
  • $\begingroup$ @WhatRoughBeast, it was specified that there are lots of bottles. He can set up more than one still. $\endgroup$ – Monty Wild Sep 21 '15 at 22:52

OK whoever proposed the seawater evaporation idea, proposed a very smart thing indeed! Evaporated (and frozen) water contains only pure H2O without any salt or whatever. So evaporating and condensing seawater will leave the salts back in the evaporating kit and only water will condense.

First things first, you'd need to find out which island it is. If it's on the map, all the better. If not, find your latitude/longitude coordinates with gps (it comes installed with several laptops) and email them to the search and rescue of your country's naval guards or whatever. Or maybe contact the nearest nation if it's not at daggers drawn terms with yours.

For water intake, you would need to find some edible, bulbous roots or tubers. If there are coconuts on the island (there should be), your food problem is already solved for days.

Build a fire by the leaves & dry twig rotation method (it will take an hour or two, but yes, it works) and keep it lit. It will signal any ships passing near your location. If there are no snakes on the island, you should have no trouble sleeping at night. If there are snakes on the island, it means there's small game for you (which is good!).

In short, locating your island on the map, sending your location coordinates to rescue authorities is your primary concern. Meanwhile find a drinkable water source (or create it with evaporation) and survey the island for food sources. If/when you have signaled your location to rescue authorities, shutdown your laptop and don't waste the battery except for checking out responses to your request.

  • $\begingroup$ To comment on the first paragraph, you could even look for a bird, steal her egg and then you have salt with new purpose! $\endgroup$ – Stephan Bijzitter Sep 21 '15 at 8:29
  • $\begingroup$ Thats vevy cruel :( $\endgroup$ – Youstay Igo Sep 21 '15 at 8:44
  • $\begingroup$ Note that while coconuts are good short term, in the long run they are not a balanced diet! $\endgroup$ – Tim B Sep 21 '15 at 9:15
  • $\begingroup$ I wonder someone would be striving to survive, let alone thinking about turkey roasts and pizzas ... Of course this is a quick survival guide. And it is hard to find a long term high nutrient food source on an island that doesn't have fruits or fauna to hunt. $\endgroup$ – Youstay Igo Sep 21 '15 at 9:42
  • $\begingroup$ Please stop talking about pizzas guys, my stomach has enough conversation about this topic right now. $\endgroup$ – varnaud Sep 21 '15 at 16:09

To distil yourself water, you'll need a heater, a source of "dirty" water, something to condense the steam on and something to catch the distilled water in.

For your heater, make a wick out of a strip torn off your clothing and fit it in a bottle of rum. Use a spare laptop battery to get the wick alight.

The middle piece of your distilling contraption needs to be an empty bottle filled with sea water, placed directly over the wick of the heater.

The third piece of your contraption is another rum bottle - this time held at an angle above the middle bottle. This is your condenser. You want this bottle cold, so use bottles of rum out of the cave and rotate them periodically for best results. Once you start using up rum and have spare empty bottles, you can use sea-water too.

Finally, water vapour will condense and run off to the lowest point of the angled bottle, where you position a clean bottle. If the drops are dropping all over the place you can make a crude funnel - either with bits from an old battery, smashing one of the empty bottle carefully, etc.

The gap between the heater and the bottle of seat water does not have to be very big - the heater bottle could be buried in the sand and then a couple of rocks or even more bottles strategically placed partly in the sand could be used to fashion a tripod which holds the bottle full of sea water in place. The bottle capturing distilled water drips can also be on the sand. Finally, the "distiller" bottle of cold rum/sea water could be hand held - it would take a fair bit of attention span to ensure the condensed water drops are falling into the collection bottle and to avoid being burnt by steam, but if this proves too difficult the condensed water can be mopped up with a piece of fabric and then squeezed out into the collection bottle instead (i.e. don't try condense enough water that it forms tiny stream of water running down the bottle - just as soon as it has anything condensed on it, wipe it up with a cloth and once the cloth is wet enough, squeeze it into the collector and repeat).

A crude diagram of your desired setup

  • $\begingroup$ Thanks for the schematic. Words are starting to make less and less sense to me. For the heater, it's clothes inside a rum bottle (with rum inside for combustible)? I'm not a Molotov expert, but is this gonna really works or just burst into flames? And how long can it keep going until the rum runs out, assuming 1.14 liters bottles? $\endgroup$ – varnaud Sep 21 '15 at 16:03
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    $\begingroup$ Yeah, a strip of t-shirt or shoelace as a wick (assuming its a natural fabric, you won't have much luck with synthetics). It'll definitely work if the rum has a high enough alcohol content - alcohol fuelled hiking stoves are quite popular in real life. Depending on the burning surface area, the quality of the rum, wind, etc etc means the total burn time is super variable. As a rough estimate, 1.14 liters of rum with a single wick should last around 6 hours (around 30ml / 10 mins). $\endgroup$ – mccdyl001 Sep 22 '15 at 8:04

Based on your scenario, you have rum and an internet connection. Use the internet connection to order some pizza or Chinese food delivered, then feed the delivery guy the rum until he's too drunk for him to notice your stealing his boat.
Now you're home free, the boat will have everything you need to get back to civilisation, and history will remember you as the guy who freed the world of the terrors of long distance pizza delivery, you'll be a hero.


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