Sunday, April 6, 2014

Learning to act right (40)… Skating on thin ice…

Torrey Orton

April 6, 2014


 Learning to predict a terminal fall at the boundary between solid and fluid


Learning to calculate risks is a basic achievement for the conduct of everyday life. I’m talking here of things like how many steps to take in one bite on the way up or, more saliently, down life’s stairways. How good is my chance of crossing the street against the lights between legal crossings without getting scrunched by the bus coming one way and the truck from the other? Cultural variants on this theme, and adult opportunities to re-experience childhood learnings, can be found here: .


As these things do, the idea of my learning to skate on thickening ice came into recent view. Especially to skate on clear ice. Clear ice means this: when you walk on it you can see straight into the water. On very clear ice it’s hard to tell that the ice is there. It is the colour of the underlying water. I grew up looking down a hill big enough to provide an extremely beginners ski slope (20 meter rise) onto a small New England pond (about 200 meters by 50 meters), the sort which seems to make up about ¼ of the surface area of the region.


We started learning about ice when we were in nappies…which is to learn about the progress of winter from turning of the leaves to slight freezing of the ground with increasing periods of frost on grass and puddles along the way to earth frozen to a concrete consistency and ice carrying a hundred people sliding around with greater and lesser finesse. Snow may or may not appear anywhere along this transition.


So by age four or five we would amble down to check the pond’s willingness to be crossed dry-footed. New ice can be safe yet cracking, the progress of skating being a pushing along the wave of the ice flowing down and up as one passes. If you haven’t experienced this phenomenon, tough. I can’t think of a similar elsewhere in nature except for a lava flow which fails the similarity test by starting with death from the ride rather than ending with ice, though ice is also greatas the poet said (Robert Frost, appropriately, in Fire and Ice, refusing to complete the implicit ‘nice’ for a rhyme).


Then, there was the problem of varying ice depth across the pond, arising from the faster flow of the stream part of the pond in some areas, and not just the obvious ones near where the stream ran into it and out of it. This danger is perceptible with practice (usually including some drops into the water). Skill growth is marked by a reduction in the number of feet dropped together and how far (also feet in those days!). Skill improvement requires the perennial favourites: cautious and a delicate testing touch with toe or stick, often noted by their absence among risk takers.


What we learned to solve here was a repeated pile of rice problem: at what height of added grains will it collapse. For skaters the collapse of the ice will be wet feet at least and drowning at most. Learning to judge the risk involves a lot of factors underpinned by the ignorant fearlessness of the young and sustained by their invariable superiority to adults in perceptual sensitivity and reflex action speeds, coupled with their relative lack of weight! A rice collapse will just be a mess, unless you are in a storage silo.


I don’t know that I’d try a newly glazed pond surface these days, but my chance of seeing one are slim. I don’t usually go north for winter. That dogs and deer often fail this learning test is one sign of its difficulty, especially when the ice surface is snow-covered – a degree of difficulty in discernment beyond most people’s capability.

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