around before lying down on the hearth rug. In the dearest dog friend we have, is something just a little untamed, and that seems to be what we need to connect our lives with all the beauty and mystery of natural things.
HOW DOES A SPONGE HOLD WATER?
Do you want to be told? It’s more fun to find things out for yourself. Get the smallest glass tube that is sold in drug stores. Put one end of it into a glass full of water and see what happens. The water rises in the tube a little higher than it stands in the glass No one knows just why it does this. It is thought that the wall of a tube has an attraction for the tiny molecules of water, and pulls them up a little way. The finer the tube the higher the water is drawn up into it.
Now a hair is a very small, hollow tube. The sponge is made up of hair-like hollows that pull up or, as we say, soak up water. The Latin word for hair is capillary. So this force is called capillary attraction. Sugar, salt, starch, chalk, sponges and the hairs of animals and fibers of plants have capillary attraction. You can prove this by dipping threads, strings, pieces of cloth, the edge of a lump of sugar or salt in a liquid, and watching the water climb. It is by capillary attraction that water is pulled from the roots to the farthest leaves of tall trees. The water it not only pulled up, it is held up. If the hair tubes of a sponge or a towel are too full, some of the water falls or drips away, but most of it is held until it is evaporated into the air.
WHY SOME PEOPLE ARE LEFT-HANDED
Are you left-handed? If you are, very likely it worries mama and papa and all your teachers. It shouldn’t worry them. And really it is a great waste of useful time to try to make you right handed. The trouble—if it is a trouble—is in the brain. For some reason that no one understands, the nerves of our bodies cross over, so the right side of the brain controls the left side of the body, and the left brain the right side. Usually the left brain is a little the larger, so it takes command and makes the right side of the body leader. When, about six times out of a hundred, the right brain is larger, it makes the left side leader. It is supposed that the left brain in most people gets more blood because the heart is on the left side. This makes ninety four or five people out of every hundred right-