Here’s a product that I did not know about previously and have not used myself: Sodium acetate hand warmers. These little goop packets contain a supersaturated liquid solution of sodium acetate dissolved in water. They also contain little metal discs that, similar to the cap from a Snapple bottle, make an audible click if you squeeze them through the pouch.
Supersaturation is a weird idea. It’s as if there’s some maximum amount of salt that can be dissolved in a liquid before it crystallizes, but if you just put a little bit of care into the dissolution process then you can blow right through that limit, going headlong into supersaturation. But supersaturated solutions are delicate, and if you disturb them just a little bit — decrease the solution’s temperature, or introduce a seed crystal, or just shake them up a bit — then all of a sudden the whole thing will crystallize rapidly, releasing heat as it does. This is the principle behind sodium acetate hand warmers: Grab one of these pouches, and click the metal disc inside it with your thumb, and the sodium acetate will come to its senses and solidify into sodium acetate trihydrate. The crystallization reaction is exothermic, with a latent heat of crystallization around 264–289 kJ/kg; this heat is released over about a half hour, warming your hands and pockets and whatever else is nearby. Then, when the reaction has been exhausted, you can boil the pouch in water, turning it back into a supersaturated liquid that just waits around to crystallize again.
I find it relaxing to think about this chemical solution, flipping between its solid and liquid phases. But I can’t tell whether the relaxation phase is the solid one, which is brittle and tense, or the supersaturated liquid, which stands on high alert for anything that might kick off crystallization.
Now that I’ve learned about sodium acetate, I somewhat regret having recently purchased iron oxide hand warmers in advance of a ski trip with my kids. These little packets, which I remember fondly from the ski trips of my youth, contain powdered iron, which reacts with atmospheric oxygen to produce iron oxide. This is to say, they rust. The rust reaction is, in a hand-wavey sense, reversible (grid scale iron-air batteries operate on a similar, and reversible, principle). But my hand warmers only go one way, down the chemical potential energy hill. Then they sit there, in their little energy holes, presumably for a long time. Which must be, now that I think about it, a more relaxed state than the sodium acetate hand warmers experience.
Something I think I know about myself is that I can experience relaxation through work. Or some work, I should say, some of the time. Anyway it happens, every once in a while, that I assign myself a piece of work and then find myself totally at peace, moving from motion to motion, switching from task to task, identifying and then overcoming one problem after another. The experience is non-reversible, but when it’s over I feel recharged.
Scope Creep
- This Thursday, at noon ET, the SOW Members’ Reading Group will be discussing Ian Hacking’s scientific-philosophical essay, “Do We See Through a Microscope?” You can join us, with a nice discount, by signing up as a Member today.
- Related to microscopes: Traditional optical microscopes show us all of the light originating from a single viewport, no matter which focal plane it originates from. On the other hand, confocal microscopes block all out-of-focus light, resulting in images with increased resolution and contrast. Confocal microscopy was invented by none other than Marvin Minsky, who went on to co-found MIT’s AI lab and then be named, later and in graphic detail, in a deposition related to Epstein and Maxwell.
- Something I remembered recently from childhood: Jim Abbott was born in 1967 in Flint, Michigan. He was born without a right hand. In high school he became both a pitcher and a quarterback, excelling at both positions. He was drafted by the Blue Jays right out of high school, but decided to go to the University of Michigan instead, where he kicked considerable collegiate butt. After college he was drafted again, as the eighth overall pick, and signed with the California Angels. In his second season in the majors he had the fourth-lowest ERA of any pitcher in the American League, and two years later, playing for the Yankees, he threw a no-hitter against the Cleveland Indians. In his last year in the majors Abbott was traded to the Milwaukee Brewers, where he was required to bat as well as pitch; he went two for twenty-one, scoring runners on each of his hits. With one hand.
- The word “serendipity,” which I’d define roughly as “pleasant randomness,” has its origins in the word “Serendip” — an antiquated name for the place we now know as Sri Lanka.
- In linguistics, a mora is a sub-syllabic unit of timing. Syllables are composed of mora, and in some languages (Japanese among them) the number of mora in a syllable can determine its linguistic weight.
- The next time I’m in Boston, I want to visit Harvard’s incredible-looking collection of glass flower replicas. Made by a German father and son around the turn of the twentieth century, the replicas are intricate and botanically accurate; this blog post explains how and why they were made.
- Diatoms are single-celled microalgae, which collectively generate between twenty and fifty percent of all the oxygen produced on earth. Diatoms “constitute nearly half of the organic material found in the oceans.” Their decomposed shells go on to produce the nutritious marine sediment that, blown from the Sahara desert west across the Atlantic ocean, fertilizes the Amazon basin.
- It’s not exactly seasonal, but nonetheless I find resonance with the spirit represented in “Yes, Virginia, there is a Santa Claus”:
Nobody sees Santa Claus, but that is no sign that there is no Santa Claus. The most real things in the world are those that neither children nor men can see… Nobody can conceive or imagine all the wonders there are unseen and unseeable in the world.
You may tear apart the baby’s rattle and see what makes the noise inside, but there is a veil covering the unseen world which not the strongest man, nor even the united strength of all the strongest men that ever lived, could tear apart. Only faith, fancy, poetry, love, romance can push aside that curtain and view and picture the supernal beauty and glory beyond. Is it all real? Ah Virginia, in all this world there is nothing else real and abiding.
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