During the Middle Ages the application of fluid machinery slowly but
steadily expanded. Elegant piston pumps were developed for dewatering
mines, and the watermill and windmill were perfected to grind grain, forge
metal, and for other tasks. For the first time in recorded human history significant
work was being done without the power of a muscle supplied by a
person or animal, and these inventions are generally credited with enabling
the later industrial revolution. Again the creators of most of the progress are
unknown, but the devices themselves were well documented by several
technical writers such as Georgius Agricola