Science!

If you expend a good deal of your shaving energy mentally, as I do, trying to anticipate the biological effects of the applied cosmetic potions (under penalty of pain), then this video ought to BLOW... YOUR... MIND!

https://www.youtube.com/watch?v=CNQf9vZqv7k

The food coloring is powered by one of shaving's very own moisturizers, propylene glycol. I strongly suspect that any alcohol would do. This is obviously the vaguely remembered "water displacement" from my biology class in slide preparation. Evaporation in the video stands in place of liquid diffusion, but just about everything we do to our skin has to do with the general principle.

https://en.wikipedia.org/wiki/Marangoni_effect

Why do sensitive-skinned (or, simply, if you prefer, "adequately moist") shavers prefer cold water? Surface tension is temperature-dependent: the "mass transfer" that ultimately brings pain is thus limited in the most general way.

Why does pure glycerin sit harmlessly on the surface of my scars at night, but wreak holy hell on my nerve endings when combined with soap? Soap makes the solution miscible with oil (the "waterproofing" of the skin barrier) by drastically lowering its surface tension.That's why soap is called a "surfactant." And, why does glycerin make shaving soap easy to lather? It is specifically mentioned in the wiki: "the Marangoni effect stabilizes soap films."

Finally, I note the probable root of witch hazel's effectiveness: the way my cured Witch Hazel beads up in my cup and my hand, it seems that it would increase interface surface tensions within the epidermis. In other words, it isn't counteracting the glycerin, but the soap!

The Book That Launched a Blog


I'm not sure how I hit upon it in the same session of googling, but this seems like a good time to temper our enthusiasm. Just the wiki is a thought-provoking read.


I've been thinking of the direct-stroking, glycerin-infused school of shaving as "incommensurate" with my own. It isn't just because of how I've been treated on bulletin boards, or undue respect for the market in books and glycerin soap, that I don't criticize ridiculous assertions like Leisureguy's recent: "conventional razors [...] cut purely with compressive force." In today's three shaves per blade, dehydrated skin paradigm, an old razor instruction pamphlet wouldn't seem to falsify that statement.

But, as Veritasium also pointed out, social media aren't science. The very real problem that the false "paradigm," which is really just corporate destruction of culture, cannot solve, is us: the so-called "sensitive skinned." Our position clearly calls for further philosophical consideration along Kuhn's lines, even if it is a cliched bastardization.

Today, my Gillette Slim did something that even Ruby could not: tamed the Racer. Taking a hint from the slant, I used 5-7-9 (factory) settings, cured witch hazel and Williams. Gillette adjustables fall cleanly within the classic paradigm, not the neotraditional, as I suspected at first.

1 comment:

  1. https://www.newscientist.com/article/dn3408-oil-and-water-do-mix-after-all
    I've oddly just circled back to this by studying the brewing of kombucha... 100% boiled "nute" is different than reconstituted. Could be a new way to understand distilled water (which is chemically "de-gassed"); I want to know how once-boiled, cool water could facilitate scent integrations and waterlogging stubble.

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