Monday, January 3, 2011

Hoarfrost, icehouses and switching seasons

It's been really cold the last few days; clear and cold.  My farm is in the bottom of a river valley, and on days like this, the cold air pools in the valley, so when it's 20 degrees other places, it's 5 degrees at the farm.  It's nice in the summer. 
2700 years ago people took this winter cold and move it into the summer.  They'd saw big blocks of ice out of the local ponds and stack them in ice houses. In the USA in the last couple of hundred years these stored blocks of ice would last all year, and you'd get a regular delivery of winter to a chute in your kitchen, or to your icebox on your back porch.  The ice wagon would either come if you called them (called as in walked to their shop -- remember, phones are a relatively recent invention) or scheduled a regular dropoff. 
 The house that I live in now has an ice chute that was imperfectly patched at the back of the house.  It was lined with galvanized iron.  I thought it was a coal chute at first, but it goes into the kitchen area -- coal was usually stored in the basement around here. 
 In July I'll look at these pictures and wish that I had this cold. 
 Each crystal forms, and then branches out.  They're very delicate; a few minutes of sun or the slightest touch will disrupt them. 
 Successive days will freeze progressively deeper layers in the water.  You can measure the intensity of the cold around here by how thick the layer that froze is.  here, the top layer was a pretty cold day.  the middle day, cold, but not as much. 
 When the top of the water freezes and the water below leaves, it gives you these miniature riverscapes, decorated with little trees, all flocked. 
 This puddle is about as big as a bathtub. 
 they're interesting looking at whatever distance you choose.  Closeup you can see that they have even more details.  Fractal-like. 

1 comment:

Dean Smith said...

I can remember the ice house on our farm. It was right across the lane from the milk house -- the place where the cream separator was and where the milk was stored in stainless steel milk cans in a water bath until the dairy truck came to pick them up. The ice must have been used in the summer to help cool the milk.