Adventures in Ethics and Science

Last weekend, while I was still in the throes of grading, my better half decided to take the Free-Ride offspring on a hike (or, in the Free-Ride vernacular, a “death march”). The younger Free-Ride offspring reports back on some of the salient details.

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Dr. Free-Ride: Can you tell me what you saw on your death march by the bay?

Younger offspring: We saw lots of cool things. One of them was a snake skin. And we saw lots of pickleweed, which we tried.

Dr. Free-Ride: Oh, you tasted it?

Younger offspring: Uh huh. I only like the salty bits.

Dr. Free-Ride: What kind of critters did you see there?

Younger offspring: I saw a jackrabbit.

Dr. Free-Ride: Cool!

Younger offspring: I was the one who pointed it out.

Dr. Free-Ride: Where was it?

Younger offspring: It was running up the trail. And then we saw a ground squirrel.

Dr. Free-Ride: Hmm.

Younger offspring: We saw lots of …

Dr. Free-Ride: Yes?

Younger offspring: Swallows. (I was trying to remember the name for them.)

Dr. Free-Ride: Did you see any fish or other bayland creatures of note?

Younger offspring: No fish, but [Dr. Free-Ride's better half] saw a lizard.

Dr. Free-Ride: Neat. And then, you also brought something home from the death march.

Younger offspring: Salt. Actually, it’s a rock with salt on it.

Dr. Free-Ride: Now, I understand from [Dr. Free-Ride's better half] that you wanted to bring the snake skin home, and you were not allowed to.

Younger offspring: Uh huh, because other people wanted to enjoy it.

Dr. Free-Ride: Sure.

Younger offspring: And I wanted to bring the salt-rock home and [Dr. Free-Ride's better half] let me because there were a lot more of them there for people to discover.

Dr. Free-Ride: Oh, so it was a matter of relative scarcity, it was.

Younger offspring: Uh huh.

Dr. Free-Ride: That’s cool, that’s important. We want to share the nature with the other people who come out to see it so they can discover just as many interesting things as we did.

Younger offspring: Yeah.

Dr. Free-Ride: What’s interesting about the salt-rock?

Younger offspring: It’s interesting because I never saw salt on rocks.

Dr. Free-Ride: So, it’s a rock that has crystallized salt on top of it?

Younger offspring: Uh huh.

Dr. Free-Ride: And it washed up on the edge of the bay in one of the pools where the water is really salty?

Younger offspring: I think — I didn’t taste the water to see if it was salty. But there were a lot more big hunks of salt there. Some we even can’t lift up and bring home, some were really too big!

Dr. Free-Ride: Interesting.

Younger offspring: And we’re going to do an experiment with it.

Dr. Free-Ride: Oh? What experiment are you going to do?

Younger offspring: Try to dissolve it.

Dr. Free-Ride: What do you think will happen?

Younger offspring: I think the salt will dissolve but the rock won’t.

Dr. Free-Ride: After you dissolve it, do you think the salt will be dissolved forever, or do you think the salt will be able to come out of solution and form salt crystals again?

Younger offspring: It will be able to come out.

Dr. Free-Ride: We could try that with sugar, too. Did you know that?

Younger offspring: Yeah.

Dr. Free-Ride: That’s how you make rock candy. So maybe that could be a side-by-side experiment with dissolving the salt and then trying to get the salt crystals back out.

Younger offspring: So how about near dessert time we could do the rock candy experiment?

Dr. Free-Ride: My dear, getting the crystals out of solution is going to take a little more time than that!

Comments

  1. #1 Super Sally
    May 30, 2008

    Good ploy on the snake skin!

    You know my longstanding rule: “No reptiles (or parts thereof) in the house”.

    Glad you’ve all emerged from the 4th circle of grading …

  2. #2 Warren
    May 30, 2008

    Look out on the crystallization process. I tried that once many years ago. The supersaturation worked fine — actually too well. I poured the solution into a can and set it in the garage on a workbench.

    When I checked on the progress of the crystal growth a couple days later (it was a hot summer), the water had already evaporated and the can — and a significant portion of the bench — were covered with new crystalline growth.

    Retrospectively, a few sheets of waxed paper under (and around) the can would probably have been a good idea.

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