Sometimes even dreams can lead to inventions. Elias Howe had been trying for a long time to invent a sewing machine, but he could not make his machine work very well. After another long day of failure, Howe gave up and went to sleep. That night he dreamed that he was being chased by wild men carrying strange spears which had holes in their points. When Howe woke up, he remembered the dream, and his problem was solved. He put the eye of the sewing machine needle at the pointed end, and his invention worked.
Have you ever heard of a paper house? A paper house is built with paper tubes. They are used for walls, doors, and windows. Paper becomes strong when it is rolled into paper tubes. So the paper house is strong enough to stand. It is also warm enough. The heat doesn't go out of the paper house quickly because the paper tubes have air in them. Paper houses are used as temporary houses. They have two good points. First, it is easy to build them and break them down. Second, we don't need much money to build them.
In England we hardly have any skiing. The reason is very simple: we hardly have any mountains ― and not much snow. So we think of skiing as an aristocratic sport. It is for those who are rich enough to go to Switzerland for the winter. When I came to Japan, however, I was so surprised to find almost all my students planning to go skiing during the winter holidays. They didn't have to go all the way to Switzerland, of course. Here, almost on their front doorstep, they had the Japanese Alps; and these Alps were covered with snow almost all winter.
Astronauts' bodies change in space. For example, they get about 1.5 inches taller. Their hearts get smaller because the blood in their bodies moves up to their heads. Also, bones and muscles get weak. To keep their bones and muscles strong, astronauts must exercise 90 minutes every day. In space, astronauts can also have problems with their teeth. Their dental fillings can cause pain. Dentists check the astronauts' teeth before they leave earth. They check for air under the fillings. Air under a filling can cause a toothache in space.
The smile may no longer be an effective way to mask one's true feelings. Some psychologists have claimed that true smiles and false smiles use different muscles. For example, in the true smile, the muscles surrounding the eyes tighten, while the cheek muscles pull the corners of the lips upward. On the other hand, in the false smile, the muscles between the eyebrows move slightly, while the muscles around the mouth pull the corners of the lips downward. If the psychologists' claim is proven to be true, perhaps people will worry less about what they say and more about which muscles to use when they smile.
