“How do I use a Galileo thermometer?”

Photo: Shala Howell

As you can see, our storm glass still isn’t back to normal. So Mommyo has declared that this is the week The Nine-Year-Old and I finally learn to use the Galileo thermometer Daddyo gave us all those years ago.

Let’s start with the basics.

“How do I read a Galileo thermometer?” 

This is the easy part. To read a Galileo thermometer, look at the bubbles floating near the top of the tube. The label on the lowest bubble tells you the temperature.

As I type this, the label on my lowest floating bubble reads 24°C.

Aye, there’s the rub.

All the labels on our Galileo thermometer are written in Celsius. (Front and back, sadly.)

We live in a Fahrenheit world here at Caterpickles Central, so 24°C doesn’t really mean much to us.

“How do I convert temperatures from Celsius to Fahrenheit?”

These days, the absolute easiest way to convert from Celsius to Fahrenheit is to Google it. There are entire web pages devoted to eliminating that little bit of math from our lives.

But here at Caterpickles, we believe that the easiest road isn’t always the best road, even when Math is involved, so here’s the math behind those temperature conversion tools.

To convert from Celsius to Fahrenheit, you multiply the temperature by 9, then divide by 5, and add 32.*

In Math-speak, that’s

(°C × 9/5) + 32 = °F

Clear as mud? Let’s do a sample problem.

If the Galileo thermometer reports a temperature of 24°C in Mommyo’s office, what is the temperature in Fahrenheit? 

Step 1: Multiply by 9.

24°C x 9 =  216

Step 2: Divide the result by 5.

216 / 5 = 43.2

Step 3: Add 32.

43.2 + 32 = 75.2°F

75.2°F feels about right, actually.

The Nine-Year-Old, sadly: “Mommyo, do I really have to do all that math every time I want to use the Galileo thermometer?”

Mommyo, hard-heartedly: “Yes. Or you could learn to think in Celsius.”

The Nine-Year-Old: “But no one speaks it here.”

Mommyo: “Tell you what. Let’s do all the math one time and use it to make a chart. We’ll keep that chart next to our Galileo thermometer so that we can know what all the labels mean.”

The Nine-Year-Old, grudgingly: “Oh all right. But you have to do all the even-numbered ones.”

Mommyo, pointedly: “They are all even numbers.”

The Nine-Year-Old, factually: “You’re the one who wants to use this thing.”

So much for integrating math into our daily lives.

Here’s our chart, in case you’d like to skip all that pesky math as well:

The Nine-Year-Old, curiously: “Mommyo, how does the Galileo thermometer know what temperature it is, anyway?”

That, my little Caterpickle, is a question for next week. Who knows? We might even do a bit of experimenting to see if the theory actually works.

Related Links: 

*Fun Fact: To convert from Fahrenheit to Celsius, you do the reverse. First subtract 32, then multiple by 5, then divide by 9. Or, if you prefer the math:

(°F − 32) x 5/9 = °C

About Shala Howell

I spent two decades helping companies like Bell Labs, Juniper Networks, and a genetic testing company that was later acquired by CVS translate some of the world’s most complicated concepts into actionable, understandable English. Now I'm working on a much harder problem -- fostering children’s curiosity and engagement in the scientific, artistic, and linguistic world that surrounds them. The first book in my Caterpickles Parenting Series, What’s That, Mom?, focuses on how to use public art to nurture children’s curiosity in the world around them. My next book, Did Dinosaurs Have Belly Buttons?, is currently planned for release in 2018. In the meantime, you can find me blogging about life with a very curious Ten-Year-Old at Caterpickles.com, chatting about books and the writing life at BostonWriters.blog, and tweeting about books, writing, science, & things that make me smile at @shalahowell.
This entry was posted in Can we do that sometime?, Science and tagged , , , , . Bookmark the permalink.

One Response to “How do I use a Galileo thermometer?”

  1. Pingback: “How does a Galileo thermometer work?” | CATERPICKLES

What are you thinking?

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s