But their efficiency greatly improved when it was discovered that more power could be produced when the sails or blades were attached to a horizontal shaft that jutted out of a tower.
ولتدوير حجر الطاحونة في الاسفل ،‏ وُصل العمود الافقي بآخر عمودي بواسطة مجموعة من المسننات .‏