Elasticity. Traction. Torsion. Flexure. Tenacity. The Most Tenacious Metal. Ductility. Malleability. Hardness. Alloys. Resistance. Persistence. Conductivity. Equalization. Reciprocity. Molecular Forces. Attraction. Cohesion. Adhesion. Affinity. Porosity. Compressibility. Elasticity. Inertia. Momentum. Weight. Centripetal Force. Centrifugal Force. Capillary Attraction. The Sap of Trees. Sound. Acoustics. Sound Mediums. Vibration. Velocity of Sound. Sound Reflections. Resonance. Echos. Speaking Trumpet. The Stethoscope. The Vitascope. The Phonautograph. The Phonograph. Light. The Corpuscular Theory. Undulatory Theory. Luminous Bodies. Velocity of Light. Reflection. Refraction. Colors. The Spectroscope. The Rainbow. Heat. Expansion.

VIII. HOW DRAUGHTING BECOMES A VALUABLE AID Page 95

Practical Mechanics for Boys — Part 2

Lines in Drawing. Shading. Direction of Shade. Perspectives. The Most Pronounced Lines. Direction of Light. Scale Drawings. Degree, and What it Means. Memorizing Angles. Section Lining. Making Ellipses and Irregular Curves. Focal Points. Isometric and Perspective. The Protractor. Suggestions in Drawing. Holding the Pen. Inks. Tracing Cloth. Detail Paper. How to Proceed. Indicating Material by Section Lines.

Practical Mechanics for Boys — Part 2

Annealing. Toughness and Elasticity. The Process. Tempering. Tempering Contrasted with Annealing. Materials Used. Gradual Tempering. Fluxing. Uniting Metals. Alloying Method. Welding. Sweating. Welding Compounds. Oxidation. Soldering. Soft Solder. Hard Solder. Spelter. Soldering Acid. The Soldering Iron.

Practical Mechanics for Boys — Part 2

Spur and Pinion. Measuring a Gear. Pitch. Diametral Pitch. Circular Pitch. How to Order a Gear. Bevel and Miter Gears. Drawing Gears. Sprocket Wheels.

The Lever. Wrong Inferences from Use of Lever. The Lever Principle. Powers vs. Distance Traveled. Power vs. Loss of Time. Wrongly-Directed Energy. The Lever and the Pulley. Sources of Power. Water Power. Calculating Fuel Energy. The Pressure or Head. Fuels. Power from Winds. Speed of Wind and Pressure. Varying Degrees of Pressure. Power from Waves and Tides. A Profitable Field.

Horse Power. Foot Pounds. Energy. How to Find Out the Power Developed. The Test. Calculations. The Foot Measure. Weight. The Gallon. The Metric System. Basis of Measurement. Metrical Table, Showing Measurements in Feet and Inches.