(Rob Kingston) said:John Laird <[email hidden]> wrote in message news:<[email hidden]>...
Quoted message said:Spotted on Saturday morning in the middle of a stream bed. There was
nothing above this, and the focus of attention is about 4" high:
http://www.laird-towers.org.uk/pics/walks/ice1.jpg
and a closer view:
http://www.laird-towers.org.uk/pics/walks/ice2.jpg
I have my own theory as to how this formed, but am curious to see if others
have their own ideas, or have seen something similar.
Further to my last post, this page has a better explanation of this
particular phenomenon:
http://www.newscientist.com/lastword/article.jsp?id=lw243
(snip)
Interesting. Something I (fiendishly) did not mention was that the small
tower was not wholly ice. There was in fact a stalk of grass in the middle
(and you can see others embedded in the ice around it). I had a few
theories, one being that the puddle had frozen across the surface but not
around the grass, allowing water to be forced up around the stalk as the ice
expanded. Such things have been seen in ice-cube trays, apparently, if a
small hole on the ice surface is left open. However, in relation to the
size of the puddle, the small ice tower is quite large and also very smooth.
I then thought perhaps there was some kind of capillary action going on, but
I figured the whole thing would freeze solid at an early stage. That left
me considering whether the effect was in fact due to condensation - the
grass picked up moisture from the air which then froze. This could continue
ad infinutum provided moist air was still being blown past. I would be at a
bit of a loss to explain why you might not find many solitary blades of
grass so encrusted, but this was on a sheet of gritstone with almost no
vegetation around. The stream bed would be depressed from the surrounding
vegetation, permitting lower temperatures to form. And there was running
water nearby to increase the humidity.
Well, I thought it was interesting anyway. I "apologise" to the thread
police for the poor choice of subject title.
[Also spotted in the gorge was a boulder almost entirely encrusted in about
1/2" of clear ice, on which were some lovely "boils", no doubt the product
of water splashing onto ice and freezing. However it was all I could do to
use the boulder to navigate across sheets of ice without going a over t.
Couldn't get close enough with my camera for that one.]
Quoted message said:I'll leave it to others to return the topic to walking 😉
I don't know about you, but I've been putting one foot in front of the other
since I was about 10 months old. I sort of take it for granted, and prefer
to discuss things wot I have seen while walking !
--
I couldn't repair your brakes, so I made your horn louder.
Mail john rather than nospam...
