For a discussion of SCA Sciences you should see the Sciences article
Scientific progress, as we think of it, was limited during early period. Scientific thought bloomed during the Renaissance, when "proper" scientific method was developed and the study of the world became separate to the teachings of religion.
Progress toward the Scientific Method
Anton here (6/11/03) :
The above is a very nineteenth century view that has been extensively challenged in recent years.
On the theory side,Albertus Magnus and [Roger Bacon] are two examples of medieval thinkers who embodied the scientific method.
Another, even less known, example is Albertus Magnus' finest student St Thomas Aquinas (yeah, *the* Thomas Aquinas, the one all you Catholic schoolkids were made to read) - although he very seldom ventured out of Philosophy or Theology into what we would recognise as Science.
Here is two of his comments on discussion of Ptomely's scheme of how the stars work
'The suppositions that these astronomers have invented need not necessarily be true; for perhaps the phenomena of the stars are explicable on some other plan not yet discovered by men' (in Lib. ii. de Coelo, lect. 17).
'The reason alleged does not sufficiently prove the position; it only shows that when the position is assumed, the effects follow naturally. Thus in astronomy the system of eccentrics and epicycles is argued from the fact that the assumption enables us to explain the sensible phenomena of the motions of the heavenly bodies; this argument, however, falls short of a convincing proof, for possibly the phenomena might be explained on some other supposition' (Sum. Theol., i. q. 32, art. 1, ad. 2)
Note the emphasis on knowing the "sensible phenomena" (ie observation by the senses) and then coming up with a falsifiable theory ("some other plan not yet discovered by men") to explain it ... if Thomas had been more interested in optics, or the motion of bodies, then the history of thought could be quite different ("I bounced out of my Theology degree when I failed the Physics unit").
I am deeply indebted to Joseph Rickaby's "Scholasticism" for this, available via the Jacques Martinian Center web site at http://www.nd.edu/Departments/Maritain/etext/scholas1.htm
On the practical side, the medieval era saw a large number of technical innovations in bridge building, architecture, metallurgy, ship building, the magnetic compass and so on - the Ancients may have had more high theory, but the medieval world had a genius for putting science to work.
A decent summary of medieval applied science is Frances and Joseph Gies' book "Cathedral, Forge and Water Wheel"