Cattle, why if they run round in meadows may thunder be expected, 1122 Ceiling, how did Mr. Sands walk on the, 664 Champagne, why does it effervesce, 806 Champagne, why do bubbles rise from it in two or three columns, 807 Charcoal, why is it dangerous to burn it in rooms, 20 LESSON XV. Charcoal fires, why do they not give flames, 107 Charcoal, what is it, 275 Charcoal, why does it act as a disinfectant, 809 Chicory, what is it, 1196 Chimney, why does it cease smoking after the fire has been lighted a little while, 680 Chimney, why does a long one create a better draught than a short one, 681 Chimneys, why do some smoke when windows and doors are closed, 683 Chimneys that stand under elevated objects, why do they smoke, 685 Chimneys, why do sooty smoke, 687 Chimneys, why do they smoke in damp and gusty weather, 688 Chimney, why does it smoke when first lighted, 679 Chocolate, what is it, 1194 Circulation, why are the venous blood and chyle sent to the lungs, 887 Circulation, what is the course of the arterial blood, 888 Circulation, why does the blood impart vitality, 891 LESSON XVI. Circulation, how do we know the blood is alive, 892 Circulation, why does the blood circulate, 893 Circulation, how is the body renewed by the blood, 894 Circulation, how does the blood return to the lungs after it has reached the extremities, 895 Circulation, why are the veins more perceptible than the arteries, 897 Circulation, why when we prick the flesh does it bleed, 893 Circulation, what occurs during the, 899 Circulation, what becomes of the matter collected by the blood, 901 Circulation, how is the blood propelled through the arteries, 916 Circulation, why are the capillary vessels capable of receiving the quantity of blood sent through larger vessels, 917 Cinnamon, where is it produced, 1239 Cleanliness, why does it promote health, 1015 Clothes on fire, why should persons throw themselves down, 252 Clothing, why do some articles feel cold, and others warm, 120 LESSON XVII. Clothing, are conductors or non-conductors the warmer, 121 Clothing, why are white and light-coloured articles cool, 218 Clothing, why are dark-coloured dresses worn in winter, and light in summer, 230 Clouds, what are they, 373 Clouds, why do we not see them ascend, 375 Clouds, why are they invisible when they rise, but become visible when they have ascended, 376 Clouds, why do they not descend to the earth, 377 Clouds, at what altitudes do they fly, 378 Clouds, how many descriptions are there, 379 Clouds, what produces their various shapes, 380 Clouds, what are their dimensions, 381 Clouds, how are they affected by winds, 382 Clouds, what do Cirrus foretell, 389 Clouds, what do Cumulus foretell, 390 Clouds, what do Stratus foretell, 391 Clouds, what do Nimbus foretell, 392