Cut batts to length by setting the top of the batt into the space and cutting against the bottom plate with a sharp utility knife. Leave an extra 1/2 in. of length for a tighter fit. We're using unfaced batts that are sized to friction-fit into standard stud spaces (either 16-in. or 24-in. on-center studs).
History of Windmills. The Persians seem to have been the first to develop windmills (between 500 and 900 A.D.). Sails had long been used to move ships at sea, but the Persians converted the wind for use in grinding grain.
William Kamkwamba. To power his family's home, young William Kamkwamba built an electricity-producing windmill from spare parts and scrap â starting him on a journey detailed in the book and film The Boy Who Harnessed the Wind..