Pat, I'm not saying that water coming out of a 
cup isn't true.  I'm saying that water exploding 
far out of a c far enough to damage your eye is 
rare.  I have had water boil over from a cup.

earlier, Pat Ferguson, wrote:
>John,
>
>I have actually had water blow out of a cup in 
>the microwave, or even on the counter, after 
>I've taken it out of the microwave. I've had 
>this happen with gravy, and there was some 
>grease in the broth so it really made a mess.
>
>It does sound unbelieveable, but unless you have 
>had it happen, it's hard to believe. I've had it happen several times.
>
>Pat Ferguson
>
>At 03:54 PM 8/30/2006, you wrote:
>>Phil, from snopes, true, but rare.  I put in 
>>for a search string, heating water in a 
>>microwave.  After clicking on a link, I snipped this:
>>
>>Origins:   Exploding water? In a nutshell,
>>Too hot to handle
>>    yes, water can "explode" in the fashion 
>> described above. However, it takes near
>>perfect conditions to bring this about, thus 
>>"exploding water" is not something the
>>average hot beverage drinker who would 
>>otherwise now be eyeing his microwave with
>>trepidation need fear. Odds are, you'll go 
>>through life without ever viewing this
>>phenomenon first-hand, and if you're one of the 
>>rare few who does get to see it,
>>you will likely not be harmed by the experience 
>>(that would take your standing right
>>over the cup at the instant it happened, and 
>>the liquid's bolting up and hitting
>>your skin).
>>  The Food and Drug Administration (FDA) has advised consumers:
>>  This type of phenomenon occurs if water is 
>> heated in a clean cup. If foreign materials
>>such as instant coffee or sugar are added 
>>before heating, the risk is greatly reduced.
>>If superheating has occurred, a slight 
>>disturbance or movement such as picking up
>>the cup, or pouring in a spoon full of instant 
>>coffee, may result in a violent eruption
>>with the boiling water exploding out of the cup.
>>  What Can Consumers Do to Avoid Super-Heated Water?
>>  Follow the precautions and recommendations 
>> found in the microwave oven instruction
>>manuals, specifically the heating time.
>>  Do not use excessive amounts of time when 
>> heating water or liquids in the microwave
>>oven.
>>  Determine the best time setting to heat the 
>> water just to the desired temperature
>>and use that time setting regularly.
>>   The e-mailed warning quoted above a model of 
>> non-specificity (no names, date, or
>>locale; only the detail that the "victim" was 
>>26 years old, presumably to enforce
>>the idea that this accident could not be blamed 
>>on a child's typical lack of caution),
>>leaving us able to address only its theoretical 
>>aspects.  Nearly every science writer
>>who has tackled the topic notes that the 
>>"severe superheating" phenomenon is real
>>but likely not nearly as common as the message 
>>cited above might make it sound.
>>  In an article for New Scientist, Richard Barton wrote:
>>  A portion of the water in the cup is becoming 
>> superheated — the liquid temperature
>>is actually slightly above the boiling point, 
>>where it would normally form a gas.
>>In this case, the boiling is hindered by a lack 
>>of nucleation sites needed to form
>>the bubbles
>>. . .
>>  I imagine that by keeping the cup still and 
>> microwaving for a long time, one could
>>blow the entire contents of the cup into the 
>>interior of the microwave as soon as
>>you introduced any nucleation sites. It is this 
>>sometimes explosive rate of steam
>>production that means you should take great care when using a microwave oven.
>>   From the
>>How Things Work
>>  web site:
>>  Glass containers are clearly the most likely 
>> to superheat water because their surfaces
>>are essentially perfect. Glasses have the 
>>characteristics of frozen liquids and a
>>glass surface is as smooth as... well, glass. 
>>When you overheat water in a clean
>>glass measuring cup, your chances of 
>>superheating it at least mildly are surprisingly
>>high. The spontaneous bubbling that occurs when 
>>you add sugar, coffee powder, or
>>a tea bag to microwave-heated water is the 
>>result of such mild superheating. Fortunately,
>>severe superheating is much less common because 
>>defects, dirt, or other impurities
>>usually help the water boil before it becomes 
>>truly dangerous. That's why most of
>>us avoid serious injuries.
>>   From the
>>Unwise Microwave Oven Experiments
>>  web site:
>>  Things are different in a microwave oven. The 
>> water gets hot but the container usually
>>does not. There are no "boiling-bubbles" 
>>triggered by a hot metal pot. Without those
>>bubbles to cool it, the temperature of the 
>>water rises far higher than 100C°. We
>>call this "superheated water." Superheated 
>>water is just waiting for some sort of
>>trigger which will let bubbles form and allow 
>>boiling to commence. If the water becomes
>>hot enough, a few bubbles will appear, but 
>>these quickly rise and burst, and the
>>water isn't cooled much at all. In the 
>>microwave oven, even if your mug of water
>>is bubbling slightly, don't trust it, since 
>>it's temperature has risen so high above
>>100C° that bubbles are appearing spontaneously. 
>>If some unwitting victim should pour
>>a soluble powder into the superheated water, 
>>this will carry thousands of tiny air
>>bubbles into the water. Each of these micro 
>>bubbles expands into a 1cm steam bubble,
>>and the result is a huge "explosion" of hot 
>>froth. It's just like dumping ice cream
>>into root beer, but the froth can be so violent 
>>that the hot water sprays into the
>>air.
>>   If you're worried about explosions over 
>> superheated liquid, you can virtually eliminate
>>the possibility of its happening to you by 
>>simply leaving some non-metallic object
>>(such as a wooden spoon or stir stick) in the 
>>cup or bowl when you boil liquids in
>>your microwave.  It may not be necessary, but 
>>it won't hurt anything either.  Peace
>>of mind rarely comes so cheaply.
>>
>>earlier, Phil Scovell, wrote:
>>>This is one to look up on snopes I guess but I have heard of this before and
>>>things falling apart after being super heatened in the microwave.
>>>
>>>Phil.
>>
>>John
>

John