CONTENTS 



CHAPTER PAGB 



I. HEAT 13 



II. TEMPERATURE AND HEAT 33 



III. COMMON PHENOMENA DUE TO HEAT 37 



IV. BURNING OR OXIDATION 50 



V. FOOD 67 



VI. COOKING AND ITS EFFECT ON FOOD 82 



VII. THE DIGESTION OF FOOD 91 



VIII. FOOD SUBSTITUTES AND ADULTERANTS 97 



IX. BACTERIA AND FOOD. How TO KEEP FOOD WHOLESOME . 105 



X. FUELS 118 



XL CLOTHES AND How THEY PROTECT Us 129 



XII. HOUSEHOLD CHEMICALS . . . . . . . 138 



XIII. BAKING POWDERS AND SODA 148 



XIV. YEAST AND BREAD MAKING 153 



XV. BLEACHING, BLUEING, STARCHING 158 



XVI. DYES 168 



XVII. METALS USED IN THE HOME 173 



XVIII. OILS, PAINTS, AND VARNISHES 182 



XIX. NITROGEN AND ITS RELATION TO PLANTS . . . .186 



XX. DRUGS AND PATENT MEDICINES 191 



XXI. How TO KEEP WELL WITHOUT DRUGS AND PATENT MEDI- 

 CINES 196 



XXII. SIMPLE ELECTRIC DEVICES 207 



XXIII. MODERN ELECTRICAL INVENTIONS 217 



XXIV. MAGNETS AND CURRENTS 225 



XXV. How ELECTRICITY is OBTAINED ON A LARGE SCALE . . 234 



XXVI. LIGHT - . . 240 



II 



