This is a marvellous little book. From the brief description of the evolution of the windmill with various historical examples, the author quickly moves through anemometers, horizontal windmills, to wind motors with a vertical axle and even a pantanemone, a simple precursor to the modern turbine.
The next four chapters deal in sequence with four windmills for the home builder — a working model windmill, a somewhat larger windmill that develops about 1/30 horsepower, a yet larger windmill with a sail diameter of 6' that develops about 1/10 horsepower, and then a working windmill with sails 10' in diameter that will develop up to 1/2 horsepower, suitable for pumping water or driving a dynamo, at each step providing detailed diagrams of the main components. The final chapter deals with the production of electricity by wind power.
The great value of the book is that it lets anyone engage the subject to produce something that will turn merrily in the wind, whether it is a simple anemometer or a full-blown working mill. Along the way it takes small side trips to show you how to make a simple wind-pressure gauge, or calculate the force in pounds per square foot of winds of various velocities. It makes a pleasant read, even if you never build anything.
Softcover, 5 1/2" × 8", 78 pages. First published in 1910; reprinted in 1999.