Chapter XI: Part 11

What we call hard water contains certain salts which soft water does not contain. This salt in hard water is lime or some other salts which the water has picked up out of the ground as it passed through either coming up or going down. On the other hand, we can guess after having been told this much that if we can find any water that has not passed through the ground, and, therefore, not had a chance to pick up any salts, we will have soft water. From that point it is easy to guess, then, that rain water must be soft water, and so it is. The water in the cisterns, which is rain water, is soft water, and the kind we get out of the wells is hard water.

We do not like to wash either our faces or our clothes in hard water, especially when it is necessary to use soap, because when we use soap with hard water the soap undergoes chemical change which prevents its dissolving in the water. Therefore, you cannot easily do a good job of washing in hard water. On the other hand it is easy to dissolve the soap in pure rain water or soft water and that is the kind we, therefore, prefer for washing.

How Does Water Put a Fire Out?

This is at first a puzzling question, because back in your mind is the thought that since hydrogen and oxygen are necessary to make a fire burn, it seems strange that water, which is composed of oxygen and hydrogen, will also put it out.

A burning fire throws off heat, but if too much of the heat is taken from the fire suddenly the temperature of the fire is sent down so far below the point at which the oxygen of the air will combine with it that the fire cannot burn. We speak commonly as though water thrown on a fire drowns it. That is practically what happens. Scientifically what happens is that the water thrown upon the fire absorbs so much of the heat to itself that the temperature of the fire is reduced below the point where oxygen will combine with the carbon in the burning material and the fire goes out.

To answer the unasked part of your question at the same time I will say that hydrogen and oxygen when combined as water will put the fire out rather than make it burn, more because when these gases take the form of water they are already once burned, and you know that anything, substance or gas, which has already been burned cannot be burned again. It required great heat to make oxygen and hydrogen combine and form water, and it also takes great heat to separate them again. So they are really burned once before they become water.

Where Does the Rain Go?

Eventually almost all of the rain that falls runs into the rivers and lakes and later finds its way into the ocean, where it is again taken up into the air by the sun’s rays. But many other things happen to parts of the rain which do not find their way into the ocean. In the paved street, of course, where the water cannot sink in, it flows into the gutter and thence into the sewer and on down to the river or wherever it is that the sewers are emptied. You see, it depends very much on what the earth’s surface is covered with at the place where the rain falls. When it strikes where there is vegetation a great deal of it stays in the soil at a depth of comparatively few feet. If it is soil where trees and other plants grow a great deal of it is sucked up from the ground by this vegetation and given back into the air through the leaves and flowers. Some of the rain keeps sinking on down into the earth until it strikes some substance like rock or clay, through which it cannot sink, and then it follows along this until it finds something it can get through and collects in a pool and forms an underground lake, and may cause a spring to flow. Then there are also worms and other forms of animal life in the earth which use up some of the water. But it all gets back into the air eventually to come down some time again in the form of rain.

Why Does Rain Make the Air Fresh?

The main answer to this question must be that the rain in coming down through the air drives the dust and other impurities which are in the air before it, and so cleans the air and makes it absolutely clean. In addition to this it is now stated that since very often rain is produced by electrical changes in the air, and that these electrical changes produce a gas called ozone, which has a delightfully fresh smell, it is this ozone that makes us say the air has become fresh.

The air above our cities is almost constantly filled with smoke, containing various poisonous gases, and these are driven away by the falling rain.

Then, too, there is always a greater or less accumulation of dirt, garbage and other things in the cities which give off offensive smells constantly, but which we do not notice always because we become used to them. When the rain comes down it washes the streets and destroys these smells, and that makes the air fresh and delightful to take into the lungs.

In the country the air is more nearly pure all the time, because the things which spoil the air in the city are not present.

Is a Train Harder to Stop Than to Start?

The answer is yes. It is harder to stop a train than to start it, or rather it takes more power. The speed of a train depends upon the motive power. When a train is stopped and you wish to start it, you must apply enough motive power to start it going. There must be enough power to move the weight of the train and overcome the friction of the wheels on the track. It is, of course, easier to move a thing that weighs less than a heavier one. If you throw a ball ten feet into the air, it will perhaps not sting your hand when you catch it on its return; but, if you throw it one hundred feet into the air, it will sting your hands when you catch it. Besides, it will come down faster the last ten feet of the way than the ball which you threw only ten feet into the air. This is because when movement is applied to anything you add power to it. The ball which comes down from one hundred feet in the air acquires more power in falling and it takes more power to stop it. A train in motion has not only the power of the weight of the train behind it, but also the additional weight which the movement of the train has given it. Therefore, it takes more power to stop it than to start it. To stop a train you must apply the same amount of power as is in the moving train because the power to stop any moving thing must always be at least as great as the power which is moving it.

What Makes the Knots In Boards?

We find knots in the boards which we notice in a lumber pile or in any other place where boards happen to be, because the smaller limbs which grow away from the larger limbs of trees grow from the inside as well as the outside of the tree.

When you see a knot in a board it means that before the tree was cut down and the log sawed up into boards, a limb was growing out from the inside of the tree at the spot where the knot occurs.

You will also find that the wood in the knot is harder generally than the rest of the board. This is because more strength is required at the base of a limb and in the part of the limb which grew inside the tree than in other parts, for the limb must be strong enough to support not only the limb itself, but also the smaller limbs which grow out of it.

How Many Stars Are There?

Man may never know how many stars there are. The best we can do is to figure on the number that can be seen with the largest telescopes which have been invented, for, of course, you know there must be many millions of them which to us are invisible. We have counted the stars so far as we can see them; or, rather, so far as we can photograph them. Astronomers have found that a photographic plate exposed to the stars will show more of them than can be seen by the naked eye. This is because the materials on a photographic plate are more sensitive to the light of the stars than the human eye. By this method man has been able in a way to count the stars he can see. It adds up to more than a hundred million of them. Astronomers found this out by taking photographs of the heavens at night, devoting one picture to each section, until the entire heavens had been covered, and then counting them.

MAKING LEAD BUCKLES--THE FIRST STEP IN PAINT MAKING.]

The Story in a Can of Paint

Paint such as is most frequently used is the material used for painting buildings, such as houses, barns, stores, and many others which we need not mention here. This paint is used on these buildings mostly for two very important reasons--one being to beautify the buildings, the other being to protect them from the ravages of the weather, much in the same way that your clothes protect you from the weather.

Paint such as we mention here may be regarded as the most simple and useful form. You have no doubt frequently seen the painter-man spreading paint on some building, or perchance, you have seen your father doing it, and have noticed that paint is a fluid substance looking something like cream, which is applied to the surface to be painted with a suitable brush and is brushed out smoothly. After the first coat is dry, other coats are put on in the same way until enough paint has been put on to thoroughly hide the unevenness of the lumber and making it of a uniform color.

This paint is made by simply mixing together dry powder, which is usually called pigment, with a thin, yellowish liquid which is called linseed oil. In the earlier days, the painter-man mixed this paint himself whenever he desired to use it. In these more modern times, he usually buys this paint already prepared.

Perhaps a little history of the preparation of the package of a can of paint which he buys may be interesting to you.

Let us imagine that the can of paint is white. In this case, the pigment which is used is a white powder and is made of either metallic lead or metallic zinc. The preparation of this fine white powder is very interesting and requires considerable time to perfect.

Let us consider the pigment known as white lead first. This is produced by causing metallic lead, which is of a bluish-gray color and very heavy, to change from its original form by a process which is known as “corrosion.” This corrosion is brought about by first taking the metallic lead, which at this stage exists in large pieces known as “pigs.” These pigs of lead are melted in a furnace and then molded into small, thin shapes which are buckles.

FILLING THE STACK WITH LEAD BUCKLES.]

The next step is to take an earthenware vessel, which resembles an ordinary stone crock, and first pour into it a small quantity of acetic acid, which is about the same as table vinegar. Then the crock or pot is filled up with the lead buckles.

Where this white lead is made in a large way many thousands of these pots are placed in a building, the sides of which are walled up tight, the spaces between the crocks being filled in with tan bark. After the floor has been covered with a layer of these crocks, the layer is covered with boards, in order to provide a foundation for setting in the next layer of crocks and tan bark. The layer of boards also serves as a floor to keep the tan bark from falling into the open crocks on the tier below. This procedure is followed with tier after tier until the building is completely filled.

Corrosion of the metallic lead in the pots now begins, because the tan bark generates some heat, becoming finally quite warm. This heat causes the acetic acid or vinegar to throw off vapor or steam, which attacks the metallic lead, causing it to decompose or corrode. This process goes on for many weeks (sometimes as much as fifteen or sixteen weeks), until those buckles of metallic lead have become a mass of white powder and nearly all trace of the original metallic lead has disappeared.]

WASHING THE LEAD. SCREENS COVERED WITH CLOTH REMOVE ALL FOREIGN MATTER.

After these many weeks have passed, the pots containing the white powder of carbonate of lead, as it is called, is taken out of the building where corrosion took place, and the white deposit is put through an elaborate system of refining, which is called “washing,” and, in fact, is really washed in water, and is then dried in very large copper pans. After being dried it is in the form of large white cakes, resembling pieces of chalk. These cakes are then passed through a mill, which grinds them to very fine powder, which is packed in barrels ready to be shipped and used by the paint-maker.]

Now that we have followed through the process of making the white-lead powder, or pigment, let us take a little time to study the preparation of the other white powder, known to the paint trade as “oxide of zinc.” This is prepared in a manner quite different from that of the white lead.

First the ore which is mined from the earth containing the metallic zinc is carefully selected by expert workmen and placed in a special kind of furnace, being mixed with hard coal, such as we use in our heating stoves.]

The burning of the coal causes an intensely high temperature, sometimes being several thousand degrees. This causes the zinc ore to be consumed as it were or to pass into a form of vapor. This vapor is carried through huge pipes which are several feet in diameter and extend for a long distance. While these vapors are passing through these pipes it becomes cooled. After becoming cooled it takes on the form of very fine white powder, coming from the pipes in much the same way that snow falls from the sky in the winter. This is collected and placed in barrels, after which it is ready for the paint-maker without further preparation.]

~WHERE LINSEED OIL COMES FROM~

Since we have followed the preparation of the two important white pigments used in making our can of paint, it is now important that we devote a little thought to the liquid which is to be used. This is called “Linseed Oil.” Linseed oil is of a golden yellow color, resembling the appearance of thin syrup which we sometimes have on the table. This oil is taken from the seed of the flax plant. It might better be called “Flaxseed Oil,” yet it is not commonly known by that name, but is nearly always referred to as “Linseed Oil.” Flax is grown in many parts of the world, the most important places being the United States of America, Dominion of Canada, Ireland, India and the Argentine Republic. In the United States, the seed is sown early in spring, much the same as is done with other crops, and ripens and is harvested early in the fall of the year. The harvesting and separation of the seed from the plant or straw is done very much in the same way that other crops, such as wheat and oats, are harvested. The seed is then taken to market and is ready for the extraction of the oil, which is done by men who are known as “oil crushers.”

The oil is extracted from the seed by a very simple process. Usually the seeds are heated by steaming them, after which they pass through a mill, being ground to a coarse mass, which is then placed in very powerful machines called “Hydraulic Oil Presses,” which squeeze the oil from the seed, leaving the remainder in the form of large cakes which are then ground to a mealy-like powder which is used as food for cattle and is very much prized.

The oil which has been extracted by this process is put into large tanks where it is clarified and is then ready for the paint-maker. This oil is often referred to as “Vegetable Oil” and it has one very peculiar and very important characteristic which makes it useful and necessary for use in paint. This property is that of drying or becoming solid, losing all tendency to stickiness after it has been spread out thinly and exposed to the air for a short time.

Now that we have given attention to the preparation of the most important things used in the making of our can of paint, let us look a little to the manner in which they are put together, and the result.

The oil is necessary in making paint in order to make it fluid, so that the paint may be brushed on to the wood or other surface, and also so that the pigment or powdered material which has been put into the paint will have something to hold it to the surface. The oil or other liquid which may be used is usually called “Binder” by the paint man because it binds the pigment in the paint and to the surface on which it has been spread or applied.

In a large paint factory, the two white pigments, lead and zinc, are mixed with linseed oil in large machines known as “Mixers” into a smooth paste which is then run through other machines called “Mills,” where the paste is ground very fine into large tubes where the paint is finished by mixing in enough more oil to make it of the proper thickness or consistency for brushing. In this state it can be used, but would not be entirely satisfactory because it would dry very slowly. For that reason, the paint-maker adds in a small amount of what is known as “Drier,” which causes the paint to dry much more rapidly after it is spread out on any surface.

The paint-maker may also add in a small amount of thin liquid called “Turpentine,” which also aids in the drying and the working of the paint. Turpentine is a very thin liquid which looks like water, and it is derived from the sap of one species of pine which grows abundantly in the southern portion of the United States. The sap is taken from the tree by tapping the tree or making an incision called a box, at certain seasons. After the sap is collected it is put through a heating process called “distilling,” which separates the water-white liquid, called turpentine, leaving a large mass of heavy material which is commonly known as “Rosin.” This turpentine is very useful to the paint-maker and the painter. It is also used for many other purposes.

~WHAT MAKES THE DIFFERENT COLORS OF PAINT~

The paint which we have described is the most simple kind and is white. There are many other kinds of paint used, being of many different colors. All of these different kinds require different treatment and preparation and would require many large books to explain even in a brief way.

The white paint which we have described may be colored or tinted to many different hues by adding suitable color pigments. These color pigments are of many kinds and are derived from many different sources. The vegetable kingdom is represented as well as the mineral and animal kingdoms. The linseed oil which we have already mentioned, is derived from the vegetable kingdom. This also applies to some few of the pigments. A very important instance which we might mention is a beautiful rich brown called “Vandyke Brown.” This is made from decayed vegetation which is found in swampy districts. There are many pigments derived from the mineral kingdom. White lead and zinc oxide have already been described as useful. Among colored pigments coming from this kingdom, we might mention yellow ochre, sienna, umber, cobalt blue, and many others.

The animal kingdom supplies quite a number, one of which is a beautiful red known as “Carmine.” This is taken from a small insect or fly which is found in certain tropical climates. The production of carmine is very expensive and the product is highly prized.

Another important development of the animal world is what is called “Bone Black.” This is made by taking ordinary animal bones, putting them into a suitable furnace and burning them, which really produces bone charcoal, which is refined by powdering and washing, and finally produces a beautiful black, such as used for painting fine coaches and carriages.

Why Does a Dog Turn Round and Round Before He Lies Down?

Away back in the history of the animal kingdom, when the ancestors of our domestic dog were wild, they slept in the woods or open. When they were ready to lie down, they first had to trample the grass about them flat to make a place to lie down. This became a habit and one of the instincts of the animal which has been transmitted to the dogs of today who keep it up. It is an inherited habit quite useless to the dogs of to-day.

How Is Light Produced?

You already learned that a substance called ether is found in all substances, filling the spaces between the molecules. When the molecules are made to vibrate, the ether naturally also vibrates. As soon as the vibrations become sufficiently rapid, they produce the sensation of light. These vibrations also produce heat. In heated bodies the molecules are always found to be in vibration, and a body may become so hot that it gives off light. We notice this when iron becomes red hot. Heat and light are found together in bodies in many instances. In fact, most of the light we have comes from bodies which are hot. The sun is so hot, that it is surrounded by the gases of many substances that exist as solids on earth.

We have some bodies which produce light which is not accompanied by much heat. The glow-worm, or firefly, seems to make light with little or no heat; but we do not yet know how this is done. Almost all sources of artificial light require that heat be produced before light obtained. Only such vibrations of the ether which are sufficiently rapid produce enough light to enable us to see. For this reason, a piece of red hot iron, which is made luminous by heat and whose particles vibrate less rapidly produce little light.

What Makes Rays of Light?

Whenever the ether is made to vibrate rapidly enough at any point, the vibrations go in straight lines from the source of light in all directions. A single line of vibrating particles in the ether, is known as a ray. A number of rays, that issue from one point, are said to form a pencil. A pencil of light may be produced by holding near a candle a screen, with a hole in it. Sometimes rays of light are brought together in a point, as may be done by means of a burning glass, and one of these bundles of rays is known as a convergent pencil.

A bundle of rays that lie parallel to each other forms a beam. The rays that come to us from the sun are practically parallel and are called sunbeams.

Why Does a Nail Get Hot When I Hammer It?

When we are in the sunshine, or standing before a fire, we feel hot; when we take snow or ice in our hands, they feel cold. The thing which produces these sensations is called heat. When we feel heat, it is because heat is absorbed by our bodies, and when we feel cold, it is being thrown off by them.

To answer this question, we must see how heat may be produced. If we draw a cord rapidly through our fingers, they feel hot, and if we rub a coin briskly with a cloth or our hands, it becomes warm; if we take a nail and hammer it on a hard substance, it becomes too warm for us to hold. In these instances heat is produced by retarding or checking the motion of a body. When we draw a cord through our fingers, it moves less easily; we retard its motion by gripping it and this is what makes the heat we feel. When we strike the nail with a hammer, the motion of the hammer is checked by the nail, and the faster we pound with the hammer, the hotter the nail becomes. From these experiments we learn that whenever the motion of a substance is checked, or retarded, heat is generated, and the substance made hot.

In explaining this method of producing heat, it was at one time thought that all bodies contained a substance which produced the heat and that, when rubbed or hammered, this substance was thrown off. About the end of the 18th century, however, it was shown by Benjamin Thompson (Count Rumford), that substances when rubbed give off heat. From this we learned that heat is not a substance, because the quantity of any substance, present in a body, cannot be limitless. If it were a substance which produced the heat, the supply would sooner or later be exhausted, and rubbing could no longer produce heat.

Heat produced by rubbing, or by striking substances together, is caused as follows: If two substances are struck upon each other, the whole of those substances are checked, but the molecules of the substances are made to vibrate very rapidly, and these vibrations produce the heat we feel.

How Do We Obtain Heat?

We get most of our heat from the sun. If the heat from the sun did not reach us, no living thing would exist on the earth. No plants or animals could live; the oceans and rivers would be solid ice.

Another important source of heat, is chemical action. Chemical action is what causes fire. Even when it does not cause fire, it produces a great deal of heat. When we breathe to keep our bodies warm, it is a chemical action that occurs. Fire is the most important form of chemical action, as a source of heat.

Why Does a Glow-Worm Glow?

A glow-worm is a kind of beetle which may be found in the yards and hedges in the summer time. The name applies only to the female of the species which is wingless and whose body resembles that of a caterpillar somewhat and emits a shining green light from the end of the abdomen. The male of this species has wings but does not show any light as does the female and resembles an ordinary beetle. The male flies about in the evenings looking for the female and she makes her light glow in order that the male may find her. Glow-worms are found mostly in England. There are, however, some members of the same species of beetle common to the United States. We speak of them as fireflies or lightning bugs. The female of these also is the only one carrying a light, although unlike the glow-worm she has wings and can fly.

Why Do They Call It Pin Money?

This expression originally came from the allowance which a husband gave his wife to purchase pins. At one time pins were dreadfully expensive so that only wealthy people could afford them and they were saved so carefully that in those days you could not have looked along the pavement and found a pin which you happened to be in need of as you can and often do today.

By a curious law the manufacturers of pins were only allowed to sell them on January 1st and 2nd each year and so when those days came around the women whose husbands could afford it, secured pin money from them and went out and got their pins.

Pins have become so very cheap in these days that we are rather careless with them, but the expression has continued to live although today when used, it means any allowance of money which a husband gives a wife for her personal expenses.

Pins were known and used as long ago as 1347 A. D. They were introduced into England in 1540. In 1824 an American named Might invented a machine for making pins which enabled them to be manufactured cheaply. About 1,500 tons of iron and brass are made into pins every year in the United States.

Why Do People Shake Hands With the Right Hand?

In the days of very long ago when all men were prepared to fight at any and all times because one could not know whether another approaching was a friend or an enemy, all men went armed. This was before the day of guns when the sword was the great weapon of defense.

Upon occasion when one man approached another, each had to decide whether the other came on a peaceful mission or not.

People in those days were mostly right handed as they are now and when fighting carried their swords in their right hands.

If, then, a man wished to speak with a stranger or, as might easily be necessary, to one who may even be known to be unfriendly, he put out his right hand upon approaching to show that he had no deadly or dangerous weapon in it. The other man could see this and knew from the extended open hand that no harm was intended and that the approach was peaceful. If, then, he was willing to meet the other, he also extended his right arm with the hand open to show him who was approaching that his fighting hand was empty also; and when they met each would grasp the hand of the other so that neither one could change his mind and assume a fighting attitude without the other having an equal warning.

How Did the Custom of Clinking Glasses When Drinking Originate?

In the days of the Roman gladiators, before a duel with swords, it became the custom of each of the participants to drink a glass of wine before fighting. Just before the fighting commenced two glasses of wine were brought and the gladiators drank. These two glasses of wine were provided by the friends of either one or the other of the gladiators. To guard against treachery, through some over zealous friend of the fighters furnishing poisoned wine was necessary. So before drinking and to show there was no treachery, the gladiators came close together and poured wine from one glass into the other back and forth until the wine in the glasses was thoroughly mixed. If the wine in one glass then had been poisoned, the poisoned wine would thus be in both glasses, and if there had been any treachery, both gladiators would be poisoned if they drank. The wine was poured from one glass to the other to show that there was no treachery.

This custom continued in use for a long time until the idea of drinking before a fight was abandoned. The custom, however, of showing friendliness in this way while drinking continued for a long time. Later it became a mere custom, however, to show a friendly spirit toward the one who was drinking with you, and when the danger of poisoned wine was past, the actual act of pouring the wine from one glass to another was changed to merely touching the glasses together. Thus today we have the friendly custom of touching glasses together long after the necessity of guarding against treachery while drinking has passed.

Why Cannot Fishes Live In the Air?

It is a curious thing isn’t it that if a boy falls into the water, he will drown if he cannot swim or someone does not help him out, and that if a fish falls out of the water onto the land, he will drown also, even though he knows how to swim, better than anything else he does. A boy cannot secure the air which he needs to live on if he is under the water, because there is not enough air for him there and a fish cannot secure enough air for him to live on when he is on land where the air is plentiful, because, the boy takes his air from the air itself and the fish gets his air out of the water.

To live by breathing the air we find on or above the land, it is necessary to have lungs and fishes do not have lungs. In the case of the boy under the water he would have to have gills to enable him to make use of the air which is in the water to live by and he has no gills.

A fish can only live a little while out of the water, but even so he can live longer out of the water than a boy can under the water.

Lest you read sometime of the flying fish and think they must be able to live out of the water, I will tell you before you ask the question that the flying fish never stays out of the water for more than a few seconds at a time. His flying leaps amount to little more than long leaps from wave to wave. He swims along very fast in the water, coming right up to the surface and out into the air and the speed at which he has been swimming regulates the distance he will go when he shoots into the air, as he has no means of propelling himself through the air, but only into it. He has, however, wing-like fins, which he spreads out when in the air and which enables him to glide through the air and thus remain in the air longer.

What Makes a Fish Move in Swimming?

This is a puzzling question, I am sure. Of course, you at once cause several other questions as soon as you ask this one such as the following: Does the water in front of him move out of the way and then close in behind him? If so, where does it go in the meantime? Does the fish move the water forward or up or down or what does he do?

The answer is, of course, in the movements of the fish’s tail. The fish in swimming is surrounded with water, top, bottom and all sides of him. The pressure of the water on the fish is the same at all points so that any motion made by him would have a tendency to make him move. As a matter of fact the tail in moving from side to side creates a current in the water from the head to the tail, or rather would produce an actual current if the fish remained perfectly still. Instead of making an actual current of water, the body of the fish is moved forward.

As to whether the water ahead of him opens up first and then the water behind him is a more difficult question to answer. To the appearance it would seem as if the water moved at both ends and sides at once, but according to scientific theory, the water at the head of the fish is displaced first.

Why Are Birds’ Eggs of Different Colors?

This is a wise provision of nature to help the mother birds hide her eggs away from the eyes of her enemies. In the animal kingdom every kind of life is the natural prey of some other kind of animal. A bird will have enemies which try to catch her as food. A bird cannot fight back, so must fly away when danger threatens, in order to save her life. This means that she must leave the eggs in the nest for the time being. At certain times she must also leave her nest and search for food for herself. In order that the eggs so left alone may have a better chance of not being discovered, nature has arranged matters so that the eggs take the color very much of the surroundings in which they are laid. Eggs of some birds are spotted or look like pebbles, because the mother bird lays them in the sand. Some of them are green, almost the color of the materials from which the bird builds the nest, and so the colors have a real, and to the birds, a valuable purpose.

Why Does a Hen Cackle After Laying an Egg?

The hen cackles because she is glad. She is glad because she has just accomplished something, which she was put on earth to do. If you study the life on the earth carefully with this in mind, you will discover that all kinds of life give expression in some form of gladness, when they have performed the things they are on earth for. It’s the hen’s way of expressing herself and letting the chicken world know. The dog wags his tail when he is pleased; boys and girls jump up and down when they are pleased, whether they have been doing anything commendable or not. No doubt also the actual laying of the egg causes some discomfort to the hen and the corresponding feeling of gladness would come naturally after the discomfort disappeared.

Why Will Water Run Off a Duck’s Back?

The reason that water runs of a duck’s back, is that the feathers of ducks are oily and, as water and oil will not mix, the water runs off instead of soaking in. The feathers on a duck are so thick on the body of the duck, top and bottom, that even if it were not for the oil which is on the feathers the water would have some difficulty in soaking through the feathers. But the main reason why the feathers on a duck’s back cause water striking them to run off is that the duck has an oil gland which is constantly producing grease or oil and which the duck uses in giving his feathers a thin coating of oil to make them slick with oil and when any water strikes the duck it runs off. Other birds which live in the water a great deal have this oil gland for the same reason.

THE STORY IN A STEEL RAIL

Molten iron is brought from the blast furnaces to the open-hearth furnaces, and dumped into a receptacle called a mixer, the capacity of which ranges from 400 tons to 1000 tons, depending upon the number of furnaces to be served.]

Pictures in this story by courtesy of Bethlehem Steel Co.

Charging Side of an Open-hearth Furnace.

An open-hearth furnace consists of a long, shallow hearth, suitably enclosed in fire-brick, and bound together with steel binding. The furnace is heated by burning gas and air, which have previously been preheated, so that a temperature is obtained in the furnace ranging from 2900 to 3050 degrees Fahrenheit.]

The open-hearth process consists of the purification of iron by oxidizing out the impurities and burning out the carbon of the iron until a tough and ductile steel is produced, which can be made of any desired composition by the addition of the necessary quantities of alloys just previous to tapping and pouring. The impurities in the iron are oxidized by the slag lying on top of the metal, and the burning out of the carbon, which is a very slow operation, is hastened by the addition of iron ore, the oxygen of which combines with the carbon of the iron and passes off is a gas going up the stack.

When an open-hearth furnace is ready for a charge, a variable amount of scrap, say 30 per cent of the total weight of material used for the heat, is charged into the furnace. With this scrap is charged sufficient lime or limestone to make the slag, as well as some iron ore to assist in reducing the carbon of the iron. In about two or three hours the required amount of molten iron is brought from the mixer in ladles, and poured into the furnace on top of the scrap, lime and ore.]

Molten Steel Being Poured Into Ladle.

When the scrap has all been melted, a test is taken to determine the amount of carbon remaining in the bath. Iron ore is added from time to time until the carbon in the bath has been reduced to the desired point, and the metal is sufficiently hot to pour. At this point “recarburizers” (consisting of Ferro-Manganese, Ferro-Silicon, and pig-iron, or coal) are added to get the required composition. The tap hole at the back of the furnace is opened, and the steel is allowed to run out into a ladle, the slag coming last and forming a blanket over the steel in the ladle.]

The ladle is picked up by an electric crane and carried over cast-iron moulds, which are set on cars, the steel being poured into the moulds, resulting in steel ingots. A sufficient amount of time is allowed for the steel to become chilled or set, when the cars are pushed under an electric stripper, where the moulds are removed from the ingots. After the ingots leave the stripper they are taken to the scales and weighed, and after weighing are put into the soaking pits. The pits get their name from the part they play in the heating of the steel for rolling. When the steel ingot is stripped the outside of the ingot is cool enough to hold the inside, which is still in a liquid state, and the steel is put into the soaking pits to allow the inside to settle into a solid mass, after which the ingot is reheated for rolling. The length of time in the soaking pits depends upon the size of the ingot, as the larger the ingot, the greater length of time is required to set.

When the steel is ready for rolling it is taken from the pits by overhead electric cranes, and placed into a dump buggy at the end of a roller line, which leads to the blooming mill. The dump buggy derives its name from the fact that when the ingot is placed into same in an upright position, the buggy, in order to place the ingot into a horizontal position on the roller line, dumps over, in the same way as if one were to rock too far forward in a rocking-chair, the dump buggy operating on the same principle.]

Blooming Mill and Engine.

The ingot travels down the movable-roller line to the blooming-mill rolls, which roll it down from a piece 19 inches by 23 inches to what is known as an 8 inch by 8 inch bloom, which is the size usually used in the manufacture of rails. The blooming mill derives its name from the fact that after an ingot is rolled in same it is no longer called an ingot, but a bloom.

After leaving the blooming mill the bloom travels along another roller line to the shears, where it is cut into two or three pieces, the number of pieces depending on the size of the rail which is to be rolled. The blooms are then lifted over the roller line at the shears by a transfer crane, and placed on a traveling roller line which connects with the rear of the reheating furnace. This furnace is about 35 feet long, and is so constructed that when the bloom is pushed in at the rear of the furnace, another bloom drops from the front or discharge end of the furnace.]

The Ingot Becomes a Rail.

The bloom dropping out, being sufficiently hot to roll into rails, travels along another roller line to the roughing or first set of rolls. Here the bloom is given five passes in the rolls, and is then transferred to the strand or second set of rolls, where it receives five additional passes; after this operation it is transferred to the finishing or third set of rolls, in which it is given one pass. The bloom has now been converted into a rail, and the rail travels on another roller line to the hot saw, where it is cut into 33-foot lengths, this being the standard length in this country for all rails. The rails when hot are cut by the hot saw to lengths of about 33 feet 6¹⁄₂ inches, the allowance of inches being made for shrinkage in cooling. It is difficult to believe that steel shrinks to this extent, but this is a fact, and while the rails are cooling on the hotbeds they have the appearance of being animated, as they move first one way and then the other. After the rails are on the hotbed a sufficient length of time to cool, they are taken from the hotbed and placed on a traveling roller line, which takes them to an endless chain conveyor. The statement that rails are put on hotbeds for cooling seems paradoxical, but the hotbeds are so called because the rails are placed on them while hot, and are left there until they have cooled.

The endless-chain conveyor places the rails on another bed, from which they are picked up by an electric crane and distributed to the straightening presses, where all burrs (which have been caused by the hot-sawing operation) are removed before the rails are straightened. After straightening they are transferred to drill presses, where they have holes drilled into them for the accommodation of the splice bar, after which they are placed on the loading docks.]

Who Made the First Felt Hat?

The felt hat is as old as Homer. The Greeks made them in skull-caps, conical, truncated, narrow- or broad-brimmed. The Phrygian bonnet was an elevated cap without a brim, the apex turned over in front. It is known as the “cap of liberty.” An ancient figure of Liberty in the times of Antonius Livius, A.D. 115, holds the cap in the right hand. The Persians wore soft caps; plumed hats were the headdress of the Syrian corps of Xerxes; the broad-brim was worn by the Macedonian kings. Castor means a beaver. The Armenian captive wore a plug hat. The merchants of the fourteenth century wore a Flanders beaver. Charles VII, in 1469, wore a felt hat lined with red, and plumed. The English men and women in 1510 wore close woolen or knitted caps; two centuries ago hats were worn in the house. Pepys, in his diary, wrote: “September, 1664, got a severe cold because I took off my hat at dinner”; and again, in January, 1665, he got another cold by sitting too long with his head bare, to allow his wife’s maid to comb his hair and wash his ears; and Lord Clarendon, in his essay, speaking of the decay of respect due the aged, says “that in his younger days he never kept his hat on before those older than himself, except at dinner.” In the thirteenth century Pope Innocent IV allowed the cardinals the use of the scarlet cloth hat. The hats now in use are the cloth hat, leather hat, paper hat, silk hat, opera hat, spring-brim hat, and straw hat.

What Is the Hottest Spot on Earth?

The hottest regions on earth is said to be along the Persian Gulf, where little or no rain falls. At Bahrein the arid shore has no fresh water, yet a comparatively numerous population contrive to live there, thanks to the copious springs which break forth from the bottom of the sea. The fresh water is got by diving. The diver, sitting in his boat, winds a great goat-skin bag around his left arm, the hand grasping its mouth; then he takes in his right hand a heavy stone, to which is attached a strong line, and thus equipped he plunges in, and quickly reaches the bottom. Instantly opening the bag over the strong jet of fresh water, he springs up the ascending current, at the same time closing the bag, and is helped aboard. The stone is then hauled up, and the diver, after taking breath, plunges in again. The source of the copious submarine springs is thought to be in the green hills of Osman, some 500 or 600 miles distant.

Where Do We Get Ivory?

Ivory is a hard substance, not unlike bone, of which the teeth of most mammals chiefly consist, the dentine or tooth-substance which in transverse sections shows lines of different color running in circular arcs. It is used extensively for industrial purposes and is derived from the elephant, walrus, hippopotamus, narwhal, and some other animals. The ivory of the tusks of the African elephant is held in the highest estimation by manufacturers; the tusks vary in size, ranging from a few ounces in weight to 170 pounds. Holtzapffel states that he saw fossil tusks on the banks of rivers of Northern Siberia which weighed 186 pounds each. Ivory is simply tooth-substance of exceptional hardness, toughness, and elasticity, due to the firmness and regularity of the dentinal tubules which radiate from the axial pulp-cavity to the periphery of the tooth.

How Did Trial by Jury Originate?

~WHY JURIES HAVE TWELVE MEN~

A jury consists of a certain number of men selected according to law and sworn to inquire into and determine facts concerning a cause or an accusation submitted to them, and to declare the truth according to the evidence. The custom of trying accused persons before a jury, as practised in this country and England, is the natural outgrowth of rudimentary forms of trial in vogue among our Anglo-Saxon ancestors. The present system of trial by jury is the result of a gradual growth under the English Common Law. There is no special reason why twelve is the usual number chosen for a complete jury except the necessity for limiting the number. In a grand jury the number according to law must not be less than twelve nor more than twenty-three, and twelve votes are necessary to find an indictment. The ancient Romans also had a form of trial before a presiding judge and a body of judices. The right of trial by jury is guaranteed by the United States Constitution in all criminal cases, and in civil cases where the amount in dispute exceeds $20. A petit or trial jury consists of twelve men, selected by lot from among the citizens residing within the jurisdiction of the court. Their duty is to determine questions of fact in accordance with the weight of testimony presented and report their finding to the presiding judge. An impartial jury is assured by drawing by lot and then giving the accused, in a criminal case, the right to dismiss a certain number without reason and certain others for good cause. Each of the jurymen must meet certain legal requirements as to capacity in general and fitness for the particular case upon which he is to sit, and must take an oath to decide without prejudice and according to the testimony. A coroner’s jury or jury of inquest is usually composed of from six to fifteen persons, summoned to inquire into the cause of sudden or unexplained deaths.

Can Animals Foretell the Weather?