Just curious about a peculiar observation

[Pascal_Bochet]

In article <199705240029.TAA16332 at borcim.wustl.edu>, brett at BORCIM.WUSTL.EDU 
says...
>
>>If you're a molecular biologist, there's a good chance you've experienced
>>this peculiar phenomenon before: you take a 1.5 mL eppedorf tube containing
>>about 100uL of solution (any solution, DNA, DTT, etc...) from a -20 freezer
>>before it has frozen, the solution is clearly in liquid phase, then you
>>flick the tube or you gently shake it, and as if magic by magic, the
>>solution quickly freezes within a fraction of a second, making you wait 5
>>minutes for the now frozen tube to thaw.
>>
>>Nobody I've met so far can explain it. Can any of you?
>>
>>
>>Rani
>
>It was already cold enough to be frozen, it just hadn't crystallized. 
Somehow
>flicking the tube disturbs the solution enough to begin crystalization and
>wham-o. you now have a frozen tube. happens all the time, but especially 
with

No to mention the wings of airplanes on the windscreen of cars.
Pascal_Bochet at brown.edu

>DTT and ampicillin.
>Brett Lindenbach
>Dept Molecular Microbiology
>Washington University School of Medicine
>St Louis, MO
>
>"One thousand miles an hour, I'm just like anyone.
>I want to feel the road of tar beneath the wheel
>named extinction" - Pixies
>