I would be more than happy if anyone could give some kind of answer to what were the sciences or knowledge and awarness of nature that was needed for the early frescoes to be painted.

For example, when the wet plaster dried, the pigments were chemically bonded to the plaster, how did the early painters know this would happen, or what previous knowledge allowed them to suppose and attempt to paint on wet plaster?

>For example, when the wet plaster dried, the
>pigments were chemically bonded to the plaster,
>how did the early painters know this would
>happen, or what previous knowledge allowed them
>to suppose and attempt to paint on wet plaster?

Yes, please read "Why Fresco?" article - it should help to clear a few things.
Here is the link:
http://www.truefresco.com/dcforum/DCForumID1/79.html