I built a...bitant(?) in about ten minutes

[cubinator]

This device should be able to tell you where you are to the nearest degree. Not as accurate as a proper sextant, but it's a lot less work to stick in your luggage when you go somewhere, just in case you end up on a deserted island and need to find your way home. You use it by holding it vertically so that the keychain ring hangs down, looking along the edge of the protractor at some reference point in the sky, then checking the angle made by the string and subtracting 90 from it. That gives you the height of the reference point in degrees, just like a sextant, so with this and a reasonably accurate clock you can tell where in the world you are with enough precision to make it back to the nearest continent or large island. Anyone else made any interesting devices out of common items?

[CAKE99]

9 hours ago, cubinator said:

Anyone else made any interesting devices out of common items?

I made a hat from cardboard and duct tape, several months ago I made a pair of shoes from duct tape, plastic bags and cardboard, I'm planning to make a new version soon-ish.

[p1t1o]

My practical ingenuity extends only about as far as using my piggy-bank and some string to stabilise a swishing window blind Im afraid. I did fashion a hook-on-a-stick to open/close out skylight too.

Didn't make them myself, but I had a wallet made of ducktape that lasted longer than another one made literally out of steel.

[cantab]

Does tying a plastic bag round the end of a mop to make a toilet plunger count?

[Dman979]

I can make a compass using a magnet, a needle, paper, and a bowl of water, but that's about it.

[kerbiloid]

Given:  You awake on a deserted island. In hands you hold two things occasionally grabbed when your ship sunk: a protractor and a hand grenade ring.

A stick.

 

First you need enough long and straight stick. It must be enough long and as straight as you can ever find.

When you've gotten it, you should make a staff.
Sharpen one of its ends with a flat stone — it's important. The opposite end should stay unsharpened and heavy, kinda chisels aside are even welcome.
Give it a name — say, Morning Star.

Once you've acqured a sharpened staff, first clean up your island to be sure that nothing will disturb your astronomical practices.
Use your astronomical staff as a spear-and-club tool.
This will also prove superiority of scientific experience above natural brutality.

When you feel enough safe, it's an astro time.
Find a flat place and plant your staff with its sharp end into the ground. Use your ring and rope as a plummet to set the staff vertically.
Advice: the flattest place you can ever meet is a surface of water.
Notice: it was indeed necessary to make it sharp and from scientific pov too.

Await a sunny day, and scratching marks at the end of the stick shadow, mark the noon (the shortest shadow, the closest mark to the staff).
(If you are doing this staying in a water shallow, use expendable sticks, planting them into silt).
Now you have a meridian line.
Keeping your staff and the closest stick planted, get away from them keeping them aligned and put two more sticks to make your meridian line as long as possible.
(Every next noon keep adjusting their positions).

Await the sunset and plant one more stick keeping aligned: the staff, the stick and the Sun (or another star you're orbiting).
You get the sunset direction. Repeat this in the morning with sunrise.
Repeat this procedure several months more.
(You didn't expect a fast and easy escape, did you? Otherwise you wouldn't create a sextant from protractor).

Notice: every day your daily sunrise/sunset marks drift in the same direction (left or right). It's normal and even good.
One fine day you notice that this drift stopped and even reversed. So, you marked 4 solstice directions.

Install 4 remarkable poles to designate two solstice lines. Now you have 3 intersecting lines: meridian and two solstices.
Your staff is planted in the intersection point and it is the reference point.
Rename your staff into Pillar of Morning Star.

Using a stick or so, put four marks in every solstice direction at the same distance from the staff.
Connect them and find the midpoints (measuring with a stick). You now get an equinox line (East-West direction).
Designate this line too. Now you have a complete set of eight main directions: N, S, E, W, 4 solstices.

Using the angle between these lines, study your latitude and make a sun-dial planting a stick tilted under this angle.

Also split the quadrants each in twain (points NE,NW,SE,SW). Then again. And then once again. Your get a dial of 32 nautical points.
Useless without a boat, but funny.

Scratch a set of marks along your staff. Keep constant distance between them, it's important.
Plant a short thick log to the north of your staff. Make its top saddle-shaped.

Every day kneel down before this log, put your chin onto its top and watch, which mark on the staff gives your the visible Sun altitude.
Every new or full moon kneel down before this log, put your chin onto its top and watch the altitude of the Moon.
As the eclipses happen when Sun and Moon are on the same altitude and the Moon is new or full, you can guess an approaching eclipse more probably.

Get two straight sticks and make a nunchaku binary slide rule.
Just put marks with density increaing twice every time, then do the same inside every two parks of the first order.
Make two absolutely same rules with binary logarithmic scale on them. Putting them together and sliding you can easily multiply and divide in binary system with 3-4 significant digits or even more.

Make new staff, reproduce those angular and mathematical tools on it.

 

All next year observe the night sky and notice when an especially bright star or a star cluster become first visible in the morning Sun light.
It's important. Every time you watch this, put a stick in its direction and write a day number in your notebook.

You must remember them all. Don't be afraid: every year they first rise on the same day. It's the key.
As you probably anyway don't know the star names, name them yourself. Better compose a simple story and name the stars after its characters.
As you probably also can't distinguish the constellations, combine them by yourself. Say, Big Picachoo, Small Picachoo and so on.

Every time when something important happens in nature, remark: how many days passed after the last bright star first rise.
Several years later you'll steadily tell that turnip gives its first fruits 3 days after the Left Eye of Big Picachoo first rises in the morning light.
Keep doing these observations all years after.

For your own comfort, mark such directions too. So, you will know that the Left Eye of Big Picachoo will first rise over that rock of red stone.

Pay attention: turnip on your island can grow up earlier or later (not 3, but, say 1 or 5 days after the Picachoo Day). It depends on weather, humidity, etc.
So, you should observe the planets: are they sharp or blurry.
Then, if the Left Eye of Big Picachoo rising over the Red Rock looks at foggy Jupiter, you can easily say that turnip will grow up 2 days later than average, but will be more plenty.

Attach every significant agricultural or climatic event on your island to the closest astronomical mark and a bright star.

You will notice that:
- The same star or constellation corresponds to several significant agricultural or climatic events. In brief, Big Picachoo rules turnip and autumn winds, while Small Picachoo helps him with winds and makes the underwater food sleep.
- The same direction on your dial also corresponds to several significant agricultural or climatic events. I.e. Big Picachoo, figuratively speaking, brings both turnip and aubergines from behind the Red Rock.
Adapt your mnemonic story to make it more smooth and dramatic. Let it tell how the Big Picachoo and his lesser companion brought the turnip from behind the Red Rock where they played with winds.

As the wooden sticks are nondurable, replace them with logs or even stones. If stones - don't forget to put heavy flat stones atop making triliths.
You will get your personal Woodhenge or Stonehenge where you can feel yourself as a fish in water, masterfully predicting the important events of your agricultural life.

As different parts of your agricultural year have different durations, split the year to months according to what you are doing.
Say, 45 days - a Month of Turnip Awaiting, next 16 days - a Month of Fishing and so on.
As you don't need winter - don't split it into months, let it be just a Useless Part of a Year.
Use your bright stars events as the months markers. Say, Big Picachoo brings a Month of Turnip.

After you accomplished this development, find a tribe, give them this knowledge and tell them that you must return to the Land of Druids, and they have the privilege to serve this purpose.
Or just stay and become the Great Druid, if you want.

[cubinator]

10 minutes ago, kerbiloid said:

 very big snip

Actually, I was just going to make a raft and find my way to the nearest continent, I still have to get to space you know. I might actually have some kind of boat in some cases.

[kerbiloid]

1 minute ago, cubinator said:

Actually, I was just going to make a raft and find my way to the nearest continent,

The Stonehenge builders said the same...