Termometro Lento (and a Dragon’s Bane sneak peek!)

Dragon's Bane Lo ResI’ve been hard at work writing and revising Dragon’s Bane, making the final push to get the finished manuscript completed for release in March. So for today’s post, I thought it would be fun to pair a sneak peek into the story with one of the real life objects that inspired it. But before I post the sneak peek (spoiler free!), let me add this disclaimer: my editor/proofreader has not gone over this section of the story yet. Please forgive any typos and grammatical errors! (I have a feeling I’ll be getting a phone call from her about five minutes after I post this though…haha)


From Reflection: Dragon’s Bane, Chapter 4:

The central square of Maze was flooded with vendors and festival-goers, its lines of stalls and kiosks overflowing into the adjoining streets like the sprawling arms of a giant octopus. Every path was bathed in the flickering candlelight of multi-colored paper lanterns that were suspended in neat rows between street posts, which cast the area in a rainbow of hues. Beneath those lights, the merry citizens of Maze passed from one patch of color to the next in a seemingly unbroken flow as they gradually made their way toward the towering bonfire that served as the centerpiece of the Festival of Flames.

Some of the revelers cradled bags of newly discovered baubles, while some had their hands full of delicious treats, but every one carried with them a folding fan. The fans—traditional gifts exchanged during the Festival of Fans in the springtime—were to be thrown into the bonfire as a symbol of the end of warm weather and the onset of winter.

And somewhere amidst the waving fans and laughter was Nerissa, standing and gaping in open-mouthed wonderment at the array of peculiar glass columns on display in front of her. The columns were filled with a clear liquid, and a dozen spherical bulbs floated at various levels within—each half-filled with brightly colored liquids as well.

Rian leaned around the display and made a face at her through one of the cylinders, his features comically enlarged by the curvature of the glass. At the sight of him, Nerissa clapped one hand over her mouth and looked away as she stifled a giggle.

“What are you laughing at?” he demanded, rounding the table to rejoin her with an impish grin on his face.

“I’m not laughing! As a matter of fact I’m trying very hard not to laugh,” she replied. Her cheeks twitched under the strain of maintaining a neutral expression. “Would you prefer I say instead that I find myself feeling impressed once again by your ‘stunning’ good looks.”

Rian let out a huff of feigned indignation and playfully jabbed her with his elbow. As he did so, the table holding the columns shook ever so slightly, evoking a gentle rattle from the tiny, floating bulbs.

The sound was minute, particularly in comparison to the din of the crowd, yet it summoned the vendor’s attention as surely as if they had struck a gong. She hastened over to them, wringing her apron between her hands as she spoke. “Be careful! Termometro lentos are very delicate!”

How the woman had heard such a faint sound over the crowd was a mystery to Nerissa, but a flush of shame colored her cheeks anyway. She bowed her head apologetically, and beside her Rian did the same. “We should have been more cautious. Please accept our apologies. What exactly is a termometro lento? I’ve never seen such things before.”

“You must be foreigners.” The woman lifted her chin in a show of pride, and if Nerissa weren’t mistaken, her Marisianne accent suddenly became even more pronounced.

“Everyone in the Twin Cities knows about my termometro lentos. To describe them in the most simplistic of terms, they are thermometers.”

© 2017 Rachel R. Smith


So a fun bit of personal trivia: the very first thing I bought with my first-ever paycheck (from working part time at a science and nature store at the mall) was a termometro lento (termo for short), specifically the tall one on the right in the photo below. I had my eye on it for well over a year and it took months of working to save up enough money to buy it. The scene in the sneak peek was inspired in part by events that took place on the day I finally bought mine.

My precious

“My termo” was the last one at the store–the teal color had been discontinued and our store happened to be the last in Ohio that had it. It was on display with several other termos of varying heights and colors, as it had been ever since the day I first laid eyes on it. Everyone working knew I was finally planning to buy my precious termo that night.

And then, about an hour before closing time, there came a great and terrible crash of breaking glass. Not the tiny tinkle described in the paragraphs above, but the jaw-clenching, chill-inducing horror of multiple fragile things falling like dominoes. Everyone in the store froze, someone gasped. A chemical aroma filled the air. I turned, already knowing and fearing what I would see. A woman had bumped the display with her purse, sending the termos tumbling down, one after another. Every single one on the display was broken.

Every single one except for mine, which had been miraculously spared from a shattered end.

It was taken from the display and secured in the backroom until the end of the night, and has been treated with an abundance of care for almost 20 years since. It currently enjoys a place of prominence next to a smaller and more recently acquired termo on the fireplace mantel.

And what exactly are these termometro lentos? You may also have heard them referred to by another name: “Galileo thermometer” or “Galilean thermometer.”

The termometro lento (latin for “slow thermometer”) operates based on the principle of fluid buoyancy. This is the principle that states that the density of a fluid changes in proportion to its temperature. In general, as liquids warm, their density decreases, and as they cool, their density increases. The clear liquid used in termos is not water. It’s usually ethanol, although other organic liquids can be used as well.

So in the case of the termometro lento, the orbs floating inside the glass column will rise or sink based on the changing density of the surrounding liquid, which is in turn influenced by the ambient temperature of whatever room the termo is in. The small bulbs have been calibrated and tagged to indicate what temperature they will move at. That means you can tell what temperature it is in the room by looking at the tag on the lowest bulb that is still floating. In the picture below, you can see that my living room is currently 72F. Just like the thermostat says it’s supposed to be.


If you’re wondering what is the point of having termos of varying heights, the answer is that taller termos can hold more floating spheres, which in turn means that they can measure the temperature in small degree increments. The orbs in my tall termo measure in 2 degree increments, while the orbs in my small termo measure in 5 degree increments. Basically, more orbs = more accuracy.

So, are termometro lentos any more accurate than our more modern thermometers? Nope. But let’s be realistic–is there any more beautiful way to tell the temperature? Nope. Not at all!


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