CONTENTS. 



TOOLS 

 CHAP. 



I. THE DIGGING-STICK. SPADE. SHEARS AND SCISSORS. CHISEI 



AND ADZE. THE PLANE AND SPOKEBHAVE 222 



II. THE SAW AND ITS VARIETIES 289 



III. BORING TOOLS. STRIKING TOOLS. GRASPING TOOLS . . . 249 



IV. POLISHING TOOLS. MEASURING TOOLS ....... 268 



OPTICS. 



I. THE MISSIONS OF HISTORY. THE CAMERA OBSCURA. LONG 

 AND SHORT SIGHT. STEREOSCOPE AND PSEUDOSOOPE. 



MULTIPLYING-GLABSES 276 



II. THE WATER-TELEBCOPB. IRIS OF THE EYE. MAGIC LANTERN. 



THE SPECTROSCOPE. THE THAUMATROPE 291 



USEFUL AETS. 



I. PRIMITIVE MAN AND His NEEDS. EARTHENWARE. BATJ>AND- 



SOCKET JOINT. TOGGLE OR KNEE JOINT .,. . ... . . 808 



II. CRUSHING INSTRUMENTS. THE NUT-CRACKERS, ROLLING-MILL, 

 AND GRINDSTONE. PRESSURE OF ATMOSPHERE. SBRD DIBBLES 

 AND DRILLS 320 



III. CLOTH-DRESSING. BRUSHES AND COMBS. BUTTONS, HOOKS AND 



EYES, AND CLASP , . . . . . . . . 339 



IV. THE STOPPER, OR CORK. THE FILTER . . . . 360 

 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 . v . y .-. . . . . . 376 



VII. FOOD AND COMFORT . . . . : v . . . 390 



VIII. DOMESTIC COMFORT . 40 



IX. ARTIFICIAL WARMTH. RING AND STAPLE. Ins FAN . . .412 



X. WATER, AND MEANS OF PROCURING IT ; . - , . 422 



XI. AEROSTATICS. WEIGHT OF AIR. EXPANSION BY HEAT . . 436 



XII. DITTO CONTINUED . . . . .... . . ... 447 



XTII. 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 . 618 



