About 300 years ago, Daniel Fahrenheit made and calibrated the first reliable thermometers. Some people* still use the scale he developed; the Fahrenheit Scale.

*like Americans ;-)

## Step 1: Materials and tools.

You need a small air-tight container (a 35mm film cannister is perfect), a thin translucent or transparent tube (such as an empty biro ink-tube), food colouring and something to make and seal a hole.

If you are going to add a scale, you will also need a piece of white card, clear sticky-tape and a narrow marker (an OHP pen is good).
<p>Cool!</p><p>It works really well.</p>
<p>Cool!</p>
<p>Thank you!</p>
<p>hi</p>
<p>Hi?</p>
great instructable and by the way i use farenhite scale.(more available in my country)
Thanks!
every day i search your name in the search bar and see some awesome instructables everytime!and keep commenting on them.hope many such instructables from you.(and keep replying to my comments and question. just saying!)
You don't need to search, just click on my user name, or follow <a href="http://www.instructables.com/member/Kiteman?show=INSTRUCTABLES" rel="nofollow">this link</a>.
It might just be a rumor, but I heard the Fahrenheit scale isn't totally arbitrary, 0 degrees is supposed to be the coldest temperature you can achieve with salt and ice, and 100 is supposed to be body temperature. He was a little off, but there was still method to his madness.
I thought it was defined a bit more wackily... 99 is body temperature I thought? But I remember he defined 100 to be like, the temperature cow's milk comes out as or something... It's definitely defined along those lines
Average body temperature is 98.6 degrees Fahrenheit
Sort of. 0 was the coldest he could get fluid water with salt. 100 was supposed to be body temperature, but the subject he used, his wife, had a slight fever when he established the measure. Or so the story goes...
You should read the story of how Fahrenheit determined his scale: <a rel="nofollow" href="http://en.wikipedia.org/wiki/Fahrenheit">http://en.wikipedia.org/wiki/Fahrenheit</a><br/>It is funny<br/>
Some people* still use the scale he developed; the Fahrenheit Scale.<br> <br> *like Americans (me!) &nbsp;:D
BTW: This thing is called a thermo"meter", not a "thermofahren" or a thermo"reaumur". It's a metric's, metric's world. BSG Which number had the space mission that's crashed 'cause US-nerds did not not notice that their european colleagues calculated in metrics and not in feet?
Sorry, you're wrong there. The word &quot;thermometer&quot; means &quot;heat measurer&quot;. A &quot;met<strong>er</strong>&quot; is a device for measuring. A &quot;met<strong>re</strong>&quot; is a unit of length.<br/><br/>
I hate it when people make an almost perfect correction, and then mess it up at the end: Meter is the [chiefly] American spelling for metre. Similarly, center for centre, liter for litre, etc. But yes, thermometer comes ultimately from the Greek thermos and metron, heat measurer.
What is with science teachers, Brits and biros... Biros are exactly the definition our science teacher uses for pens. <br />
For a <a href="http://en.wikipedia.org/wiki/Ballpoint_pen" rel="nofollow">certain kind of pen</a>...<br />
&quot;Nearly forty Desmonds....&quot;<br /> LOL <div id="iComment_resize_overlay">&nbsp;</div>
If you ask people, most will say that the first thermometer used the Celsius scale. It is a very common misconception. <div id="iComment_resize_overlay">&nbsp;</div>
great instructable. got to try this sometime
For all the users of &quot;imperial measures&quot; in the 3rd world: <br/><br/>Download this nice piece of software: Numerical Chameleon, and rearange all your filthy Fahrenheits, gallons, miles, mpg, oz's etc. to international reliable standards. :-)<br/><br/>DL here:http://www.jonelo.de/java/nc/<br/><br/>Greetings from the &quot;old world&quot;<br/><br/>BSG<br/>
Mine doesn't work! I have a bigger container (made for dentures, my dad's a doctor) and a smaller straw but the water doesn't even show up on the straw!!
The most likely problem is the seal, either around the straw or around the lid. Add a little modelling clay or hot-glue around any possible leak. The other thing is to make sure that there is enough air in the thermometer, since it is the air that is expanding and contracting to move the water.
I've tried straws in test tubes with and without alcohol added to the water. I've tried film canisters--same liquids. I've tried sealing the tip of the straw and leaving it unsealed. None seem to be working, even after holding in my hand and held in warm water. I'm out of troubleshooting ideas. Help!
<ul class="curly"><li>Use narrower tubes to emphasise the distance travelled by the same expansion. The inner tube of a ball-point pen is best.</li><li>Forget about alcohol - that is only used because it freezes below zero, it will evaporate from this design of thermometer.</li><li>Don't seal the top of the tube.</li><li>It is vital for the seal around the lid of the cannister, and around where the tube goes through the lid, to be utterly airtight.</li><li>When you put it together, try and start with liquid part-way up the tube, so you can see it.</li><li>Have a bigger air-gap inside the cannister - it is the air that is expanding, not the liquid. The water is just showing the movement of the air.</li><br/></ul>That do you?<br/>
i think i did this a while ago with clay clogging a straw.
I made one of these years ago. The only difference was that the instructions I followed said to add rubbing alcohol also
Hmmm...(in order to get a good seal with the straw into the cap) couldn't you just crimp the end of the straw and slide it in? A little hard to describe: Suppose you are looking down through the straw from one of the ends. Push the top of the circumference of the end of the straw down so that the top inner half circumference meets with the other inner half of the circumference and forms a u shape. Push the two points of the u together. Now poke it through a small hole in the top and pull through as necessary. For those of you couldn't suffer through or understand that description, I might post pictures (made with paint ::cringe::).
If the fit it too tight, the straw will crimp all the way along, and wreck the seal completely. It would be better to drill the hole to the exact OD of the tube.
And now behold my awesome msPaint skeels! Or not :P
aww. i thaught it would give you the actual temp :P
Sweet, I wish I had this project to do when I was a wee kid, I would have had a BLAST! ...hmmm, maybe I'll relive my childhood for just one hour.... hehehe
how could ypu have fun with a thermometer? what sort of childhood did you have?