Re: Who where the scientists that discovered Phase Changes ? How? When?

"On the 19th of December, 41923 B.C. a huntsman by the name of Boogaluk set 
out on his daily patrol. When he came to the local swamp, he found that 
instead of being soft and muddy it was hard and icy. He squatted down (it 
was much too cold to sit!) to deeply ponder the consequences ...
There is some dispute about the actual name and date, about whether it was 
he or his much more intelligent wife, and about whether it happened in 
France, Germany, or some other country ..."

Of course that is pure fantasy, but you can see that there is a problem 
about deciding who "discovers" something like phase changes!

The first person to describe phase changes with anything like our modern 
insights and understandings was the great French chemist Antoine Lavoisier

Here is an English translation of what he wrote about phase changes over 200 
years ago:

"All bodies in nature present themselves to us in three different states. 
Some are solid like stones, earth, salts, and metals. Others are fluid like 
water, mercury, spirits of wine; and others finally are in a third state 
which I shall call the state of expansion or of vapours, such as water when 
one heats it above the boiling point. The same body can pass successively 
through each of these states, and in order to make this phenomenon occur, it 
is necessary only to combine it with a greater or lesser quantity of the 
matter of fire."

Here are just a few areas where phase changes are important to us:
Weather (especially cloud formation, rain, and hail), Refrigeration, skiing 
and skating, steam engines, moulding and casting of metals, glasses, and 
plastics, crystal formation, fizzy drinks ... and the list goes on!