CHAPTER IX. AEROPLANE CONSTRUCTION Lateral and Fore and Aft. Transverse. Stability and Stabilization. The Wright System. Controlling the Warping Ends. The Curtiss Wings. The Farman Ailerons. Features Well Developed. Depressing the Rear End. Determining the Size. Rule for Placing the Planes. Elevating Plane. Action in Alighting. The Monoplane. The Common Fly. Stream Lines. The Monoplane Form. CHAPTER X. POWER AND ITS APPLICATION Features in Power Application. Amount of Power Necessary. The Pull of the Propeller. Foot Pounds Small Amount of Power Available. High Propeller Speed Important. Width and Pitch of Blades. Effect of Increasing Propeller Pull. Disposition of the Planes. Different Speeds with Same Power. Increase of Speed Adds to Resistance. How Power Decreases with Speed. How to Calculate the Power Applied. Pulling Against an Angle. The Horizontal and the Vertical Pull. The Power Mounting. Securing the Propeller to the Shaft. Vibrations. Weaknesses in Mounting. The Gasoline Tank. Where to Locate the Tank. The Danger to the Pilot. The Closed-in Body. Starting the Machine. Propellers with Varying Pitch. CHAPTER XI. FLYING MACHINE ACCESSORIES The Anemometer. The Anemograph. The Anemometrograph. The Speed Indicator. Air Pressure Indicator. Determining the Pressure From the Speed. Calculating Pressure From Speed. How the Figures are Determined. Converting Hours Into Minutes. Changing Speed Hours to Seconds. Pressure as the Square of the Speed. Gyroscopic:Balance. The Principles Involved. The Application of the Gyroscope. Fore and Aft Gyroscopic Control. Angle Indicator. Pendulum Stabilizer. Steering and Controlling Wheel. Automatic Stabilizing Wings. Barometers. Aneroid Barometer. Hydroplanes. Sustaining Weight of Pontoons. Shape of the Pontoon. CHAPTER XII. EXPERIMENTAL WORK IN FLYING Certain Conditions in Flying. Heat in Air. Motion When in Flight. Changing Atmosphere. "Ascending Currents." "Aspirate Currents." Outstretched Wings. The Starting Point. The Vital Part of the Machine. Studying the Action of the Machine. Elevating the Machine. How to Practice. The First Stage. Patience the Most Difficult Thing. The Second Stage. The Third Stage. Observations While in Flight. Flying in a Wind. First Trials in a Quiet Atmosphere. Making Turns. The Fourth Stage. The Figure 8. The Vol Plane. The Landing. Flying Altitudes. CHAPTER XIII. THE PROPELLER Propeller Changes. Propeller Shape. The Diameter. Pitch. Laying Out the Pitch. Pitch Rule. Laminated Construction. Laying up a Propeller Form. Making Wide Blades. Propeller Outline. For High Speeds. Increasing Propeller Efficiency. CHAPTER XIV. EXPERIMENTAL GLIDERS AND MODEL AEROPLANES The Relation of Models to Flying Machines. Lessons From Models. Flying Model Aeroplanes. An Efficient Glider. The Deltoid Formation. Racing Models. The Power for Model Aeroplanes. Making the Propeller. Material for the Propeller. Rubber. Propeller Shape and Size. Supporting Surfaces.