Part 45

In old people, however, wrinkles come more naturally. There it is the case of the skin not receiving the proper nourishment and attention to keep the circulation of the blood right. When people become old they are apt to lose the fat which has accumulated under their skins. If they had taken just the right amount of exercise all of their lives and kept their circulation perfect in all parts of the body, there would have been no fat there. But when the fat accumulates, it makes the skin grow larger, and then when the fat disappears and people get thin again, the skin is too large and makes the wrinkles.

Does Thunder Sour Milk?

Milk will sour in any kind of warm and moist temperature and, because just before and during a thunderstorm the air is generally quite warm and moist, it is only natural that it should turn sour. It is wrong, however, to say or think that thunder makes milk sour. Thunder is only a noise and noise cannot do anything but make itself heard. The fact that it is generally warm and moist, however, when it thunders, coupled with the fact that these conditions of the air sour milk very rapidly, have led people to connect the two in their minds and caused them to fall into the error of believing that the thunder is responsible for the change in the milk.

What Makes the Rings in the Water When I Throw a Stone Into It?

Every movement has a beginning. When a movement on the earth is once started it keeps on going until something stops it. If nothing stops it it will go on forever.

When you shout you start air waves going in every direction, which keeps on going until stopped by something which has the power to break up their waves.

When you throw a stone into the ocean you start a series of ripples or waves which spread out in every direction and if you dropped your stone into the exact middle of the ocean--half way from each side--in a perfectly calm sea undisturbed by other forces, your ring of ripples would go on getting larger until it landed on the beach or shore on each side of the ocean at the exactly the same time and there the beach or shore would stop it.

The original ring of ripples is caused by the fact that when you drop a stone into the water it disturbs the water where it goes in and the water moves away from the stone to the sides, and as the stone goes down, over and up above it, and the whole body of the water is disturbed in such a way that makes the ripple appear on the surface and spread out in every direction. As the stone goes down into the water further and further the disturbance is repeated and ring after ring appears on the surface.

Of course there are many disturbances in the water at all times. Many things may happen to break up your little ring of ripples before they touch the sides of the ocean--a ship--a fish--the wind--or one of many other things, and because this is true you would have difficulty in sending the waves made by your little pebble across the ocean, but you can take a dishpan from the kitchen and after filling it with water drop pebbles into it as nearly the middle as possible, and you will see the ripples or waves your pebble makes spread out from the point where the pebble entered the water in all directions.

Why Are There Many Languages?

Different languages developed in different parts of the world because there was no inter-communication between people in different communities, and each was really developing a language for itself. In doing so they developed their language without knowing that other communities were working out the same problems for themselves. So they first developed their own sign and gesture language and later on their word or sound language and kept on using it. While they may thus have developed the use of some of the same signs and sounds or combination of sounds to express one thing perfectly understandable to themselves, these sounds or combinations of sounds might mean something entirely different to another community, where that particular sound or combination of sounds may have been hit upon to mean something entirely different.

Of course, not all languages were developed in this way. There are, you know, a great many languages used in the world. Some of them are offshoots of others, where part of a community moved to another part of the world, taking their language with them, but developing it further along new lines, and using new combinations of sounds for new words. Then also, there are many words which mean the same thing in different languages and are spoken with practically the same sounds. This is due to the movement of people from one nation to another and bringing their own words with them, so to speak. In many instances a stranger would come to another nation, and use his own word for expressing a certain thing and that would eventually be taken up and used as a better word, and the old word dropped. It is strange that this should be true, but this accounts for the fact that many words are the same in sound and meaning in numerous languages.

What Makes a Match Light When We Strike It?

The match lights when we rub it along a rough substance, because the rubbing produces sufficient heat on the end of the match to set fire to the head, as we call it, which is made of chemicals that light more easily than the stick of wood, which is the rest of the match. The fire thus started is hot enough and burns long enough to set fire to the wooden part of the match.

To explain this more fully, let me say this. Rub your finger quickly along your coat sleeve or along the seat of your trousers, long a favorite place for men to strike matches, pretending that your finger is a match. You find the end of your finger becomes warm, don’t you? Not warm enough to set your finger on fire, of course, but if you had the same combination of chemicals on the end of your finger that there is on the match, you would set the chemicals afire and this would burn your finger, just as it sets fire to the wooden part of the match.

It took a great many years to discover the combination of chemicals of which the head of the match is made. Before that discovery was made it was far from easy to light the light in the evening as it is now. It must have been a serious thing to let the fire go out in the furnace in those days.

What Makes the Kettle Whistle?

The kettle whistles only when the water boils and the steam or gas which is the form the water turns into when boiling is trying to escape through the spout of the kettle. You see, when the water starts boiling, the inside of the kettle is at once filled with steam and more is coming out of the water all the time. This steam must get out some way, so it rushes for the spout of the kettle, and because so much of it is trying to get out of a comparatively small opening at once there is quite a pressure and this results in making the whistle out of the spout of the kettle. It is just the same process as when you whistle yourself. To whistle you fill your mouth with air and force it out through your lips, which you have closed excepting for a small opening, by the pressure you can bring to bear with the roof and sides of your mouth, and if you have learned to make your lips into the proper shape and apply the pressure steadily you can sound a very long note and make different notes by making the opening in your lips large or small. The kettle spout has only one size of opening so the sound is practically the same at all times though louder at sometimes than at others. This is caused by the varying pressure at which the steam in the kettle is being forced out.

What Makes the Water From a Fountain Shoot Into the Air?

The water from the fountain shoots into the air because water anywhere will run down if given a chance. To produce a fountain you must have a source of water supply for the fountain which is higher than the openings of the fountain out of which the water shoots. The water comes out of the holes in the fountain for the same reason that it comes out of the faucet in the kitchen or bath room. In the latter case the water comes from the waterworks reservoir in which the level of the water is much higher than the opening in the faucet in your home. Being higher the water in the reservoir is trying to get away through the pipes all the time and all the pipes leading from the reservoir are full of this water trying to get away. Just as soon as you turn the valve in the faucet the water comes out and runs down into the bowl.

If you were to turn the opening of the faucet up instead of down as it is, the water would shoot up instead of down. Not very much, it is true, but it would act much like the water from the fountain. The reason it does not shoot up high in the air like a fountain is because the opening in the faucet is the same size as the opening in the little pipe which leads the water from the street into the house. If you would turn the opening of the faucet up and attach to it a pipe which made the opening much smaller (the size of the opening in the fountains), you would see the water shoot into the air just as it does from the fountain. When you reduce the size of the opening you increase the pressure of the water coming from the pipes in proportion to the reduction you have made in the size of the opening.

Water from the fountain will not, however, shoot as high as the level of the water in the reservoir because, as soon as it leaves the pipes, it encounters the pressure of the air outside the pipes and the law of gravitation which pulls all things toward the center of the earth.

It is not natural for water to shoot into the air as it does in a fountain. The only way water can go naturally is down, and it only goes up a little way from a fountain because of the pressure of the water in the pipes behind the openings in the pipes in the fountain.

What Keeps a Balloon Up?

A balloon stays up in the air, because of the air in it, together with the weight of the balloon, is less than an equal bulk of the air in which it floats.

In former days of ballooning the balloons were filled with hot air and were then found to rise and stay up until the air inside of the balloon became of the same temperature as that in which it floated. When this stage was reached, the balloon itself would fall because the material of which it was made was denser than air.

Today balloonists fill their balloons with gas which is lighter than air, even when as cool as the air in which they rise and are thus able to stay up a long time.

You, of course, have seen many of the red, white and blue paper balloons which are sent up on the Fourth of July. You will remember that father, or whoever it is that is sending them up, lights the oil-soaked knot of cloth that is attached to the balloon immediately below the opening at the bottom. He first lights this and then holds the balloon for a time with his hands.