  Q. Why do the bubbles in a cup of tea range round the sides of the cup? A. Because the cup attracts them. Q. Why do all the little bubbles tend towards the large ones? A. Because the large bubbles (being the superior masses) attract them. Q. Why do the bubbles of a cup of tea follow a tea-spoon? A. Because the tea-spoon attracts them. Q. Why are the sides of a pond covered with leaves, while the middle of the pond is quite clear? A. Because the shore attracts the leaves to itself. Q. Why do all fruits, &c. (when severed from the tree) fall to the earth? A. Because the earth attracts them. Q. Why do persons (who water plants) very often pour the water into the saucer, and not over the plants? A. Because the water in the saucer is supped up by the mould (through the hole at the bottom of the flower-pot), and is transferred to the stem and leaves of the plant by capillary attraction, (See p. 84). Q. Why is vegetation on the margin of a river more luxuriant than in an open field? A. Because the porous earth on the bank sups up water to the roots of the plants by capillary attraction. Q. Why is a lump of sugar (left at the bottom of a cup) so long in melting? A. Because as it melts, it makes the tea above it heavier; and (so long as it remains at the bottom) is surrounded by tea fully saturated with sugar; in consequence of which, the same portions of liquid will hold no more sugar in solution. Q. Why does the lump of sugar melt more quickly when stirred about? A. Because fresh portions of unsaturated tea keep coming in contact with the lump, and soon dissolve it. Q. Why does a piece of sugar (held in a spoon at the top of our tea) melt very rapidly? A. Because as the tea becomes sweetened, it descends to the bottom of the cup by its own gravity; and fresh portions of unsweetened tea are brought constantly into contact with the sugar, till the lump is entirely dissolved. Q. How can a sick room be kept free from unhealthy effluvia? A. Vinegar boiled with myrrh, or camphor, sprinkled in a sick room, will entirely correct putridity. Q. Why does lime destroy the offensive smells of bins, sewers, &c.? A. Because it combines with the carbonic acid of these places, and converts it into carbonate of lime, which is entirely free from smell. Q. Why does chloride of lime fumigate a sick room? A. Because the chlorine absorbs the hydrogen of the stale air; and by this means removes both the offensive smell and the infection of a sick room. Q. How can the taint of meat be removed? A. Either by washing with pyroligneous acid,—covering it for a few hours with common charcoal,—or by putting a few lumps of charcoal into the water in which it is boiled. Q. Why do these things destroy the taint of meat? A. Because they combine with the putrescent particles, and neutralize their offensive taste and smell. Q. Why should bed-rooms, cottages, hospitals, and stables, be washed occasionally with lime-white? A. Because the lime is very caustic, and removes all organic matters adhering to the walls. Q. How can mouldiness be prevented? A. The perfume of any essential oil will prevent mouldiness from ink, paste, preserves, &c. Alum, salt of amber, borax, nitre, salt, camphor, charcoal, and pyroligneous acid, are all excellent antiseptics. Salt, corrosive sublimates, copperas, and alum, all arrest the decay of timber. (See p. 426.) Q. Why will strong Souchong tea poison flies? A. Because it produces prussic acid, which destroys their nervous system. Q. Why is strong green tea unwholesome? A. Because it contains prussic acid, which destroys the nervous system. Q. Why is a dead man taller than a living man? A. Because at death the cartilages are relaxed. So, also, after a night’s rest, a man is taller than when he went to bed. Q. What is sleep? A. Sleep is the rest of the brain and nervous system. Q. Why can we not see, when we are asleep with our eyes open? A. Because the “RET´INA of the eye” is inactive and at rest. Q. Why can we not hear in sleep? A. Because the drum or “tympanum of the ear” is placid and at rest. Q. Why can we not taste when we are asleep? A. Because the nerves at the end of the tongue (called papillÆ) are inactive and at rest. Q. Why can we not feel when we are asleep? A. Because the ends of the nerves (called papillÆ), situated in the skin, are inactive and at rest. Q. Why have persons in sleep no will of their own, but may be moved at the will of any one? A. Because the “cerebellum” (or posterior part of the brain) is inactive and at rest. Q. Why have dreamers no power of judgment or reason? A. Because the “cerebrum” (or front of the brain) is inactive and at rest. Q. Why are dreams such foolish and inconsistent things? A. Because the “pineal gland” is acting without the brain; and the faculty of thinking exists in the “pineal gland,” but the faculty of judgment in the “cerebrum of the brain.” The cerebrum of the brain occupies the top and front of the skull. The pineal gland is a small conical gland (about the size of a pea) in the brain. Q. Why do some persons lose all power of sensation? A. Because the “cerebrum” (or front of their brain) has been injured. Q. Why are many persons idiots? A. Because the “cerebellum of the brain” has been removed by some accident, or injured by some disease. The cerebellum is all the posterior part of the brain. Q. Why does a person feel when he is touched? A. The ends of certain nerves (called PAPILLÆ) situated in the skin erect themselves when touched, and produce a nervous sensation called feeling. Q. Why are persons able to taste different flavours? A. Because the “PAPILLÆ” of the tongue and palate erect themselves when food touches them, and produce a nervous sensation called taste. Q. Why do very old people lose the power of volition, sensation, and thought? A. Because their brain ossifies; and as the “cerebrum” (or front of the brain) goes, they lose the power of sensation and reason; and as the “cerebellum” (or posterior part of the brain) goes, they lose the power of volition. Q. Why are old people unable to walk? A. Because their muscles become rigid. |
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