CONTENTS. 



TOOLS. 



CHAP. PAOB 



I. The Digging-Stick. — Spade. — Shears and Scissors. — Chisel 



and Adze. — The Plane and Spokeshave 222 



II. The Saw and its Varieties 239 



III. Boring Tools.— Striking Tools. — Grasping Tools . . . 249 



IV. Polishing Tools. — Measuring Tools 263 



OPTICS. 



I. The Missions of History. — The Camera Obscura. — Long 

 and Short Sight. — Stereoscope and Pseudoscope. — 

 Multiplying-glasses 276 



II. The "Water-Telescope. — Iris of the Eye. — Magic Lantern. — 



The Spectroscope. — The Thaumatrope . . . - .291 



USEFUL AETS. 



I. Primitive Man and His Needs. — Earthenware. — Ball-and- 



Socket Joint. — Toggle or Knee Joint 308 



II. Crushing Instruments. — The Nut-Crackers, Eolling-Mill, 

 and Grindstone. — Pressure of Atmosphere. — Seed Dibbles 

 and Drills 320 



III. Cloth-Dressing. — Brushes and Combs. — Buttons, Hooks and 



Eyes, and Clasp 339 



IV. The Stopper, or Cork. — The Filter 350 



V. The Principle of the Spring. — The Elastic Spring. — 



Accumulators. — The Spiral Spring 360 



VI. Spiral and Ringed Tissues. — Various Springs in Nature 



and Art . ,. . " . 375 



VII. Food and Comfort 390 



VIII. Domestic Comfort 400 



IX. Artificial Warmth. — Ring and Staple. — The Fan . . . 412 



X. "Water, and Means of procuring It 422 



XI. Aerostatics. — Weight of Air. — Expansion by Heat . . 436 



XII. Ditto Continued 447 



XIII. Telescopic Tubes. — Direct Action. — Distribution of Weight. 



— Tree-Climbing. — The Wheel 460 



XIV. Paper and Moulding 472 



XV. Electricity and Galvanism 482 



XVI. Tillage. — Drainage.— Spiral Principle. — Centrifugal Force 492 



XVII. Oscillation. — United Strength. — The Dome .... 504 



ACOUSTICS. 



I. Percussion. — The String and Reed. — The Trumpet. —Ear- 

 Trumpet.— Stethoscope 513 



