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Molly Cule
331475.  Tue May 06, 2008 9:54 am Reply with quote

telegraph column -

Snowflakes
Wilson ‘Snowflake’ Bentley (1865-1931), a farmer from Vermont, became the first person to photograph a snowflake in 1885. He went on to record over 5,000 more and was the first person to claim that ‘no two snowflakes are alike’ (he also used his photomicrographic technique to record the smiles of pretty girls). In fact, we aren’t in any position to say that all snowflakes are different. There are about a million flakes in a litre of snow. A quarter of the Earth’s land surface is covered by snow each year, and this has been going on for billions of years, which means there have been countless billions of flakes. Theoretically, it is entirely possible for a pair of snowflakes to be visually identical if their environments were similar enough, either because they grew very near one another, or simply by chance. In 1988 the American Meteorological Society reported that matching snow crystals had been collected from a cloud 20,000 feet over Wisconsin (although the photos are far from convincing).

Snow Fleas
These odd, ancient creatures aren’t true fleas but a form of springtail and can sometimes found in such dense concentration they turn snow black. Like fleas, they have a cocked-spring mechanism, which means they can jump out of danger; but unlike their insect counterparts they can’t control this process and often land in exactly the same spot. They live on leaf mould, and have a handy sticky tube sticking from their undersides, which they use to anchor themselves, as well as for drinking, breathing and excreting. They are able to survive in their frozen world because of a special protein that acts as a natural anti-freeze.

Hail Cannons
At the end of the 19th Century, the ‘Grelifugue’ (hail-preventing) cannon was invented in Austria. It was thought that by blasting thunderstorms, the nuclei around which hail forms would be dispersed and fall as slush or snow instead. Initial tests in Austria were a success and hail-canon fever took off with thousands being built across Austria, Gemrnay and Italy. However, within ten years most meteorologists concluded that hail-free periods were just a natural coincidence. Despite this, hail cannons are still popular in the Mid-Western states of the USA, where hail costs agriculture in excess of a $1 bilion a year.

Snowbroth
Snowbroth is a sadly obsolete word for slush, snow that has been trodden down into a mush.

Skiing
Arthur Conan Doyle brought skiing to Switzerland. It was a common means of transport in Norway, but few Swiss practised it (they preferred snowshoes), and those that did traveled under the cover of darkness to avoid the ridicule of their peers. Doyle arrived in the country in 1893 and realised that the conditions were perfect for the sport. He taught himself the rudiments, crossed an Alpine pass and wrote up the experience in the Strand Magazine. The article not only helped make skiing less embarrassing for locals, but also established Switzerland as Europe’s premier destination for a fashionable new hobby.

Frozen food
The father of the modern frozen food industry, Clarence Birdseye (1886 – 1956) was known as ‘Bugs’ at college because of his passion for animals and he became notorious for his willingness to eat anything: starlings, blackbirds, whale, porpoise, lynx, alligator, large lizards. “I ate about everything...beaver tail, polar bear and lion tenderloin. And I'll tell you another thing-the front half of a skunk is excellent.” One of his soups combined bits of mice, chipmunks, gophers and packrats. In 1916 he moved to Labrador to make his fortune trapping foxes. Here he learnt from Eskimos how to quick-freeze (by freezing food really quickly only small ice-crystals form, so no damage is done to the cell walls of the food, preserving its texture and flavour when defrosted). In 1923 he founded his eponymous company with an investment of $7 for an electric fan, buckets of brine, and blocks of ice.

 
Molly Cule
331478.  Tue May 06, 2008 9:59 am Reply with quote

"The snow crystals . . . come to us not only to reveal the wondrous beauty of the minute in Nature, but to teach us that all earthly beauty is transient and must soon fade away. But though the beauty of the snow is evanescent, like the beauties of the autumn, as of the evening sky, it fades but to come again."

Wilson ‘Snowflake’ Bentley.

 
Molly Cule
331480.  Tue May 06, 2008 10:00 am Reply with quote

Astrologer, Johannes Kepler was the first person to do scientific research into snowflakes, in 1611 he wrote ‘On the six-cornered snowflake’, which sought to explain why snowflakes tend to be six-sided.

 
Molly Cule
331481.  Tue May 06, 2008 10:00 am Reply with quote

The Japanese scientist Ukichiro Nakaya created the first artificial snowflake; he called a snowflake a ‘letter from the sky’ as each one’s shape, size and texture are unique, determined by the temperature and moisture in the sky and the clouds through which it fell on its way to earth.

 
Molly Cule
331482.  Tue May 06, 2008 10:01 am Reply with quote

Iceland was called ‘Snowland’ before the present name caught on. It was also called ‘Butterland’ as the grass was so rich it seemed to drip butter. There are no inherited surnames in Iceland, each child takes on the first name of their father or mother as a second name and adds ‘sson’ if they are a boy or ‘dottir’ if they are a girl. The Icelandic telephone directory is arranged by first names and then by profession to minimize confusion. Non-traditional first names have to be approved by The Icelandic Naming Committee before they can be used as names. In 2006 they decided that Magnus could not be grammatically declined in Icelandic and so it was rejected as a viable name. Reykjavik, the capital means ‘bay of smokes’ because of the geothermal steam coming from the earth. 93% of Iceland’s homes are heated with this energy, saving over $100 million per year in avoided oil imports. Sofa is Icelandic for 'sleep'. http://www.icelandreview.com/icelandreview/daily_news/?cat_id=16539&ew_0_a_id=230637

 
Molly Cule
331483.  Tue May 06, 2008 10:01 am Reply with quote

Snow Creatures


Snow leopards sleep all day and hunt at night alone; there is no collective name for a group of snow leopards as they are rarely seen and if they are, they tend to be alone. Irbis is the leading premium beer in Kazakhstan, and its name means "snow leopard". The name caribou is derived from a Micmac Indian word meaning ‘snow-shoveller’. Polar bears are obviously extremely well camouflaged, only their nose sticks out, they sometimes disguise this themselves by covering their nose with their paw. If they need both hands as well as to be undercover they cover their nose with a lump of snow.

 
Molly Cule
331484.  Tue May 06, 2008 10:02 am Reply with quote

Ice skaters skate on water, not ice. Most ice rinks set their temperatures around -7°C. On the surface of any body of ice at a temperature above about −20°C there is always a thin film of liquid water, the thickness of which depends on the surrounding temperature.

 
Molly Cule
331485.  Tue May 06, 2008 10:03 am Reply with quote

Harrison Schmitt, of the 1972 Apollo 17 crew who last walked on the moon has said that he was able to glide across the moon because of is experience at cross-country skiing; he said the sliding technique is similar on both the surface of moon and the slopes of mountains here on earth.

 
Flash
331502.  Tue May 06, 2008 10:31 am Reply with quote

Molly Cule wrote:
they sometimes disguise this themselves by covering their nose with their paw

KLAXON!

 
Molly Cule
332012.  Wed May 07, 2008 5:20 am Reply with quote

aargh!!

 
eggshaped
332130.  Wed May 07, 2008 8:56 am Reply with quote

Further to supercooling; one can super-heat water.

Quote:
Liquid water will become steam at 100°C, if there already is a tiny bubble of anything (air, steam) present. But if there is no such bubble present, then the liquid will need to be heated to over 100°C to get enough energy to make that first bubble.


link

 
eggshaped
332187.  Wed May 07, 2008 10:30 am Reply with quote

Will (et al), what do you think about this:

Quote:
Although there is nothing to stop two snowflakes being exactly alike, the probability of such is microscopically small.


versus the fact that:

Quote:
There are about a million flakes in a litre of snow. A quarter of the Earth’s land surface is covered by snow each year, and this has been going on for billions of years, which means there have been countless billions of flakes.

 
Flash
332348.  Wed May 07, 2008 1:48 pm Reply with quote

What we have here is a mathematical tension between the two orders of magnitude "microscopically small" and "countless billions".

 
WB
332351.  Wed May 07, 2008 2:09 pm Reply with quote

eggshaped wrote:
Will (et al), what do you think about this:

Quote:
Although there is nothing to stop two snowflakes being exactly alike, the probability of such is microscopically small.


versus the fact that:

Quote:
There are about a million flakes in a litre of snow. A quarter of the Earth’s land surface is covered by snow each year, and this has been going on for billions of years, which means there have been countless billions of flakes.


Quite interesting. This was my first stab at a back of envelope calculation (sorry my cut & paste won't preserve superscripts - so 10[6] means ten to the power of 6 i.e. one million):

The Earth’s land area is now about 150x10[6] km[2]

Suppose a quarter of this land area is given a fresh covering of snow every day to 1cm deep, then I would say that is 0.25x150x10[6]x10[7] litres of snow. If each litre is 10[6] snowflakes, then that would be 3.75x10[20] snowflakes per day. The Earth is 4.5 billion years old. That is 4.5x10[9]x365 = 1.65x10[12] days old. Thus over the years you could say about 6x10[32] snowflakes could have fallen.

As for snowflakes, let’s say that you could distinguish (under a lens) 100 features that might or might not be present. This is 2[100] possibilities or about 10[30].

This very rough and ready maths gives us about 600 snowflakes that would be indistinguishable under the lens.


However there are a good many quibbles, and with very little juggling one could just as easily make a pretty reasonable case the other way.

 
eggshaped
332523.  Thu May 08, 2008 4:09 am Reply with quote

Will, what do you think about this:

Quote:
The likelihood of two snowflakes being alike is controversial. Our head mathematical elf has crunched the figures, and very cautiously tells us that due to the fact that there are about a million flakes in a litre of snow, and that snow has been falling for billions of years, there may have been around 600 snowflakes in the history of mankind that would be indistinguishable under a lens.


I don't want to misrepresent you, but I think the idea that the back-of-an-envelope calculation gives "600 snowflakes in the history of mankind that would be indistinguishable under a lens" is a stunningly brilliant fact.

 

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