The first windmills were developed to automate the tasks of grain-grinding and water-pumping and the earliest-known design is the vertical axis system developed in Persia about 500-900 A.D. The first use was apparently water pumping, but the exact method of water transport is not known because no drawings or designs -- only verbal accounts -- are available. The first known documented design is also of a Persian windmill, this one with vertical sails made of bundles of reeds or wood which were attached to the central vertical shaft by horizontal struts.
