When I made my monthly run to the county seat yesterday, I fiddled around until it was a little later than I’d intended because the Montana highway report said there was frost on the road surface. That means slippery. It will soon be time to watch out for frost heaves as well, which means humps of broken pavement that soon deteriorate into potholes. I’ve always been curious about frost heaves, so I went to Google which sent me to Wikipedia. I don’t like this much, but I trust it on a technical subject more than I do on anything about people or issues.
What I found was about something I’m beginning to call to myself “gradient theory.” That is, when there is more of something in one place and less of it in another, it causes movement across the boundary. There must be a more formal name for this and maybe a school of study because it is so useful, on the scale of fractals or chaos-theory and in the dimensions of simple physics like water diffusion, but also socially. (I’ll think about that later.) But this time, when I read about frost heave and other temperature-gradient phenomena, the action was microscopic and introduced a lot of intriguing new concepts.
I knew about capillary action — that liquids get drawn into a small narrow space — but had not thought about what happens when liquid water is drawn by capillary action into soil and then frozen, expanding into “needle ice.” I’d thought more in terms of seepage from the top into cracks. Water can also be drawn up plants (that’s how sap works in trees) but when these tiny columns of water are frozen they can be extruded into “frost flowers” of considerable fanciful filigree. I’d love to see some but most of the plants around here are dried out by frost time — on purpose, I’m sure.
Closely related to needle ice are ice lenses which form when there is a source of water that “feeds” the lens and grows it, maybe because there is ground water or because the soil structure lets water travel to the lens. Water tries to migrate to just under the freezing level in the soil where the ice stops it, holds it down and adds it to a lens that exerts a powerful upward force. (The freezing level moves up and down according to air temp. I never understood people saying that it “sinks” when the ground warms again. Have to think about it.)
There’s this thing called “Gibbs-Thomson effect” that is about very fine pore ice having a curvature. The higher the curvature and the more confined the lens the more likely it is to have water colder than freezing but still liquid. The surface of the lens might also have liquid water on its surface, but only a few atoms thick.
This morning on “All Things Considered” there was a story about the discovery of huge ice lenses UNDER the snow burden of the mountains of Antarctica. I don’t see an explanation of WHY there is water moving around under the ice burden. Volcanic? Springs? Warming produced by pressure? Why on mountains? They figure these lenses push the overburden ice up by meters in spite of what must be enormous weight. They also erase by melting the sedimentary layers which form a log-book of climate conditions, so the core-collectors will have to find places to drill that are not on top of lenses.
These phenomena, tiny as they are, might not move mountains, but they separate the mountains from millenia of snow.
The results on ordinary terrain are familiar enough in places where water is frequently crossing the gradient from ice to liquid or even to vapor and then back again — places like the polar caps or at the edges of winter or on other planets. The resulting geographical phenomena acquire names: palso, pingo, lithalsa. They are often geometrical — circles, polygons, stripes — that are so unorganic that people suspect alien intelligences created them. The photographs are fascinating, worth chasing on the Internet.
I’ve book-marked this website. It’s on the same trail as I am: http://knowgramming.com/metaphors/frost_heave.htm
“A crowd swells as people stream in from all directions to some place of interest. If the place of interest is a concert, the members of the audience will expend great amounts of time and energy to afford the ticket; and a change of time, energy and distance will be required to locate oneself at the event horizon. After all these energy-draining expenditures, the crowd will have accumulated – colonizing in this one place in a process strikingly similar the formation of an ice lens.
“Cool” makes for a big “draw”.
The northern plains of Montana are dependent on highway systems, so construction of roadbeds that will not accumulate or micro-shape water is vital. Therefore I’m delighted to have found “The Idiots’ Guide to Highways Maintenance”.
Much more useful than the standard practice of cursing the maintenance guys. Basically, it depends on making sure there is as little water as possible, especially from underneath, and constructing the roadbed of non-porous and therefore non-capillary-action materials. (Valier streets are mostly dirt and our water table — since we’re next to a lake — is high.)
I thought Faraday only studied electricity — indeed that’s a matter of electrons moving along a gradient — but he looked at water as well and spoke of “thermal regelation” [sic] which is that supercooled water within the lens goes across the teeny temperature gradient from “warm” to “cold” which tends to extrude soil particles to the low side and thicken the ice on the high side, so the lens rises sort of like a bubble would in water.
So now I’m thinking about social “lenses” that tend to attract some kinds of people (rich or poor, immigrant or native) and then to show signs of these same micro-migrations, person-by-person or family-by-family.
I’m thinking about concentrations of people caused by boundaries, like reservations or languages or geographical barriers. I’m thinking about (I’ve been trying to think about this for quite a while because of reading history of the rez) the “lenses” of people that form around new ideas or specific people or particular opportunities and often have enormous power to support or disrupt.
Like the Pentecostal movement, or Indian Preference, or the assignment of the more full-blood Blackfeet to the more remote Dawes allotments. (It was their preference because that’s where the hunting, firewood and water were.) Specific individuals or families have formed powerful social “lenses” — the Sandoval brothers are one of my favorite examples. Or what about the “capillary action” of the Piegan Institute which draws in children of a certain kind and propels them upward to “higher” education?
I gotta go back and look at that website about metaphors again. It is specifically for writers and teachers. What about the capillary action of the Internet and its website lenses? Or the power of simple curiosity about some pesky thing like frost.