 The Aermotor was used for pumping water for livestock and became indispensable to midwestern farmers and ranchers in the 19th and early 20th centuries.Selling only 45 windmills in its first year, Aermotor sales increased rapidly and by the turn of the century had sold hundreds of thousands of windmills.Perry also made many other refinements to windmill designs and published several windmill design patents pertaining to maintainability and efficiency.