Outdoor Water Filter - How to Make a Water Filter - The Barrel Filter

Outdoor Water Filter - How to Make a Water Filter - The Barrel Filter - excerpt from the book "The Scientific American Boy" by A. Russell Bond
Immediately after breakfast the next day we started out in two parties to search the island. The only discovery of any moment was that made by Dutchy’s party, which found a small island separated from ours by a narrow channel, through which the water ran like a mill-race.
No spring was discovered, so Uncle Ed had to construct his large filter.
Bill and I went over to Lumberville in search of a couple of cider barrels and a pailful of charcoal. The barrels were placed one on top of the other after cutting a large hole in the top of the lower barrel, and a smaller one in the bottom of the upper one.
 The latter opening was covered by an inverted saucer. Over this we spread a 3-inch layer of coarse sand, then a 2-inch layer of charcoal, a 4-inch layer of clear, sharp sand, and a 2-inch top layer of gravel. The lower barrel was provided with a faucet, through which we could draw off the filtered water as desired. In order to keep the water cool we placed the filters in a shady place near the river, and piled up earth around the lower barrel.
“Now, boys,” said Uncle Ed, “form in line there, and we will go through a fire drill.”

He arranged us about five feet apart in a line extending from the filter to the river. We had six pails, and these Dutchy filled one at a time, passing them up the line to Reddy, who emptied them into the upper barrel and then threw them back 70 to Dutchy to be refilled. Working in this way it did not take long to fill up the filter, and the burden of keeping the barrels full, instead of falling on one person, was shared alike by all.

The SCIENTIFIC AMERICAN BOY OR The Camp at Willow Clump Island
MUNN & CO., Publishers

How to Make a Simple Water Filter - The Small Filter

How to Make a Simple Water Filter - The Small Filter - - excerpt from the book "The Scientific American Boy" by A. Russell Bond
“Well, now, boys,” said Uncle Ed, wiping the perspiration from his forehead, “I am as thirsty as a whale.
Where do you get your drinking water? Is there a spring on the island?”
We told him that we used the river water.
“What, river water!
That won’t do at all,” he cried.
“You’ll all have the typhoid fever.
We must build a filter.
I brought some charcoal with me for this very purpose.”
Taking one of our pails he broke a hole in the bottom of it and stuffed a sponge in the hole.
A layer of small stones was then placed in the pail, over this a layer of broken charcoal with the dust carefully blown out, then a layer of clean sand, and finally a layer of gravel.
Each layer was about two inches thick.

The pail was suspended from a branch in a cool place and proved an excellent filter, the water trickling out through the sponge being perfectly pure and sweet, no matter how dirty it had been when poured in; but the capacity of the filter was too small, and Uncle Ed said he would make us a larger one on the morrow if no spring was discovered in the meantime.
The sun was getting low in the west, and we therefore postponed the exploration of our island until the following day.
We had been up since four o’clock that morning and had done some pretty hard work; so, immediately after supper, we turned in and, lulled by the murmuring of the river, were soon fast asleep.

The SCIENTIFIC AMERICAN BOY OR The Camp at Willow Clump Island
MUNN & CO., Publishers

How to make a Megaphone - Cardboard Megaphone

Learn how to make a  Megaphone  -  Cardboard Megaphone - excerpt from the book "The Scientific American Boy" by A. Russell Bond
A sheet of light cardboard 30 inches square was procured.
At the center of one edge a pin was stuck into the cardboard, then a piece of stout thread was looped over the pin and the two ends were knotted together just 5 inches from the pin.
Another knot was also made 29 inches from the pin. Now, with a pencil hooked into the loop, and resting first against the inner knot and then against the outer one, two arcs were drawn on the paper, one of 5-inch radius and the other of 29-inch radius.

A line was now drawn from the pin to the point where the longer arc met the right hand edge of the paper, and a dotted line was drawn from the pin to a point 1-1/2 inches from the edge at the other end of the arc. From a point 1 inch to the left of the pin we then drew a line to the left end of the arc.
With a scissors we cut the cardboard along the arcs and straight lines, all but the dotted line, leaving a piece of the shape shown in Fig. 55.
This piece was rolled into a cone with the right edge 59 lapped over the left edge and lying against the dotted line. In this position it was held by means of several brass fasteners of the kind shown in Fig. 56.
A mouthpiece was formed out of a block of wood in which a large hole had been drilled. The block was then cut away until the walls were quite thin. The hole was reamed out at the top, as shown in Fig. 57, and the outer surface was tapered so that the small end of the megaphone would fit snugly on it.

The SCIENTIFIC AMERICAN BOY OR The Camp at Willow Clump Island
MUNN & CO., Publishers

Why do Boats Float on Water?

Why do Boats Float on Water - Do you know why some things float while others sink? It isn't just because of their size or their weight. If you can float when you go swimming, why does a small pebble sink? The answer is that floating or sinking depends on an object's density. If an object is more dense than water, it sinks. If it is less dense than water, it floats.
An object is more dense than water if it weighs more than the same amount, or volume, of water, Pebbles are made of gritty particles, which are very heavy and packed together tightly. This is why they sink. They are more dense than water.
Steel has a higher density than water, so why doesn't a steel boat sink? The answer is that the inside of a ship is hollow and contains air. It also contains other materials which are less dense than water. The density of the whole ship is less than that of water.

What to do During a Tornado - Tornado Safety rules

What to do During a Tornado - Tornado Safety rules

What to do During a Tornado - Tornado Safety rules  - While different kinds of storms bring different kinds of danger, some basic safety rules apply to all storms. To be safe you should learn what kinds of storms affect the area where you live or are visiting, and you should become familiar with the safety rules for those storms.

You can use the Federal Emergency Management Agency’s (FEMA) Project Impact Web page to find the hazards for any part of the United States.
If you are in the United States, you should buy a special weather radio, which picks up broadcasts of regular weather reports and storm watches and warnings from the National Weather Service.
When the Weather Service announces a watch, it means that a particular kind of storm is possible. A warning means that a storm is headed for your area.
The best weather radios automatically turn on and sound an alarm when the nearest Weather Service office issues a warning. The online Federal Emergency Management Agency Library includes links to dozens of guides that can help you prepare for any kind of disaster.

Avoiding the dangers of lightning and floods

Lightning and floods kill more people in the United States than any other storm hazard.
To avoid being hit by lightning, stop all outdoor activities and get into a sturdy building when you see a flash of lightning or hear a clap of thunder.
Don’t take shelter under trees or in an open picnic shelter. A vehicle with a metal roof is a safe place if you roll up the windows.
When a hurricane threatens, you should heed any orders to evacuate areas that could be flooded.
You should also find out if any nearby streams are subject to flash floods. If so, leave if you hear a flash-flood warning.
Whatever you do, don’t drive your car onto a flooded road, even if the water looks shallow. Most flood accidents in the United States occur when vehicles drive into floodwater.

Taking shelter from the wind

Tornadoes, severe thunderstorms with winds faster than 89 km/h (55 mph), and hurricanes all produce potentially deadly winds.
When such a storm threatens, don’t waste time opening windows.
The biggest danger from high winds comes from the things they blow around, including objects such as garbage cans and parts of buildings.
Flying debris outside the house can hit a window and send glass flying all around a room.
If possible, take shelter in a basement.
If not, get into a small room with no outside windows, such as a bathroom or central closet.
Anyone who lives in an area where tornadoes or hurricanes hit, and whose home isn’t likely to be flooded by a storm surge or flash flood, should build a safe room, which can serve double duty as a storage room and as a shelter from storm winds when needed.

How do Storms Form - The Basic Science of All Storms

All storms have two things in common: low atmospheric pressure at the storm’s center, and winds that are created by the flow of air from higher pressure outside the storm toward the low pressure at the center.
Wind, in other words, is air that’s being pushed by high pressure toward low pressure.
Areas of low air pressure occur because the Sun heats the Earth unequally.
The Sun shines down almost directly on Earth’s tropical regions near the equator, heating this region more than the polar regions around the North and South poles and the middle latitudes between the poles and the tropics.
Storms, along with ocean currents, redistribute heat from the tropics to the middle latitudes and the poles. Without storms and ocean currents, the tropics would grow hotter and hotter until the oceans boiled.

In other words, the Sun’s heat powers the weather.

Air pouring into an area of low pressure from all sides rises because it doesn’t have any place else to go.
As air rises, it cools, and if it cools enough the water vapor in the air begins to condense.

This condensation creates the tiny drops of water or tiny ice crystals that make up clouds.
Under the right conditions, the tiny water drops or ice crystals merge to fall from the cloud as larger water drops of rain or ice crystals of snow. This is why storms bring clouds and usually bring rain, snow, or other kinds of ice.
The University of Illinois Weather World 2010 Project’s Clouds and Precipitation Web page provides detailed information on how this works.

Red Blood Cell Diseases

One of the most common blood diseases worldwide is anemia, which is characterized by an abnormally low number of red blood cells or low levels of hemoglobin. One of the major symptoms of anemia is fatigue, due to the failure of the blood to carry enough oxygen to all of the tissues.

The most common type of anemia, iron-deficiency anemia, occurs because the marrow fails to produce sufficient red blood cells. When insufficient iron is available to the bone marrow, it slows down its production of hemoglobin and red blood cells.
In the United States, iron deficiency occurs most commonly due to poor nutrition.
In other areas of the world, however, the most common causes of iron-deficiency anemia are certain infections that result in gastrointestinal blood loss and the consequent chronic loss of iron.
Adding supplemental iron to the diet is often sufficient to cure iron-deficiency anemia.

Some anemias are the result of increased destruction of red blood cells, as in the case of sickle-cell anemia, a genetic disease most common in persons of African ancestry.
The red blood cells of sickle-cell patients assume an unusual crescent shape, causing them to become trapped in some blood vessels, blocking the flow of other blood cells to tissues and depriving them of oxygen.

Where are white blood cells produced?

Blood is produced in the bone marrow, a tissue in the central cavity inside almost all of the bones in the body. In infants, the marrow in most of the bones is actively involved in blood cell formation. By later adult life, active blood cell formation gradually ceases in the bones of the arms and legs and concentrates in the skull, spine, ribs, and pelvis.
White blood cells, Red blood cells and platelets grow from a single precursor cell, known as a hematopoietic stem cell. Remarkably, experiments have suggested that as few as 10 stem cells can, in four weeks, multiply into 30 trillion red blood cells, 30 billion white blood cells, and 1.2 trillion platelets—enough to replace every blood cell in the body.
The majority of white blood cells have a relatively short life span. They may survive only 18 to 36 hours after being released from the marrow. However, some of the white blood cells are responsible for maintaining what is called immunologic memory. These memory cells retain knowledge of what infectious organisms the body has previously been exposed to. If one of those organisms returns, the memory cells initiate an extremely rapid response designed to kill the foreign invader. Memory cells may live for years or even decades before dying.

Memory cells make immunizations possible. An immunization, also called a vaccination or an inoculation, is a method of using a vaccine to make the human body immune to certain diseases. A vaccine consists of an infectious agent that has been weakened or killed in the laboratory so that it cannot produce disease when injected into a person, but can spark the immune system to generate memory cells and antibodies specific for the infectious agent. If the infectious agent should ever invade that vaccinated person in the future, these memory cells will direct the cells of the immune system to target the invader before it has the opportunity to cause harm.
Platelets have a life span of seven to ten days in the blood. They either participate in clot formation during that time or, when they have reached the end of their lifetime, are eliminated by the spleen and, to a lesser extent, by the liver.

Where are Red Blood Cells Produced?

Blood is produced in the bone marrow, a tissue in the central cavity inside almost all of the bones in the body.
In infants, the marrow in most of the bones is actively involved in blood cell formation.
By later adult life, active blood cell formation gradually ceases in the bones of the arms and legs and concentrates in the skull, spine, ribs, and pelvis.
Red blood cells, white blood cells, and platelets grow from a single precursor cell, known as a hematopoietic stem cell. Remarkably, experiments have suggested that as few as 10 stem cells can, in four weeks, multiply into 30 trillion red blood cells, 30 billion white blood cells, and 1.2 trillion platelets—enough to replace every blood cell in the body.
Red blood cells have the longest average life span of any of the cellular elements of blood.
A red blood cell lives 100 to 120 days after being released from the marrow into the blood.
Over that period of time, red blood cells gradually age.

Spent cells are removed by the spleen and, to a lesser extent, by the liver. The spleen and the liver also remove any red blood cells that become damaged, regardless of their age.
The body efficiently recycles many components of the damaged cells, including parts of the hemoglobin molecule, especially the iron contained within it.

What is the Function of Blood Plasma?

What is the Function of Blood Plasma?

What is Blood Plasma?

Plasma consists predominantly of water and salts. The kidneys carefully maintain the salt concentration in plasma because small changes in its concentration will cause cells in the body to function improperly.
In extreme conditions this can result in seizures, coma, or even death.
The pH of plasma, the common measurement of the plasma’s acidity, is also carefully controlled by the kidneys within the neutral range of 6.8 to 7.7. Plasma also contains other small molecules, including vitamins, minerals, nutrients, and waste products.
The concentrations of all of these molecules must be carefully regulated.

Plasma is usually yellow in color due to proteins dissolved in it. However, after a person eats a fatty meal, that person’s plasma temporarily develops a milky color as the blood carries the ingested fats from the intestines to other organs of the body.

Plasma carries a large number of important proteins, including albumin, gamma globulin, and clotting factors.
Albumin is the main protein in blood. It helps regulate the water content of tissues and blood. Gamma globulin is composed of tens of thousands of unique antibody molecules. Antibodies neutralize or help destroy infectious organisms.
Each antibody is designed to target one specific invading organism. For example, chicken pox antibody will target chicken pox virus, but will leave an influenza virus unharmed.
Clotting factors, such as fibrinogen, are involved in forming blood clots that seal leaks after an injury. Plasma that has had the clotting factors removed is called serum.
Both serum and plasma are easy to store and have many medical uses.

Desalination for Kids - What is Desalination?

Have you ever swum in the sea and accidentally swallowed some sea water?
It probably made you gag and cough. Sea water contains a lot of salt and this makes it very unpleasant to taste, as well as unhealthy to drink.
If you were to drink salt water, you would become thirsty.
Do you know why?
You already have lots of salt in your body— everybody has!
If you take in even more, you would feel the need to drink some liquid to water down, or dilute, the extra salt.
We can make good use of both the water and the salt in the sea, but we need to separate them first.

People in some countries in the world are so short of fresh water that they are even thinking about towing icebergs from Arctic regions to their own dry lands!
Ninety-seven per cent of the world's water is found in the oceans and seas.
Fresh water can be made by taking salt out of sea water.

Desalination process

This process, called desalination, is expensive because it needs large amounts of energy, and the salt wears away the equipment.
Saudi Arabia produces over 442 million gallons (1.7 billion liters) of fresh water each day by desalination.
In the desalination process, the salt water is boiled and quickly turned into steam. The steam then condenses into fresh water.

Glaciers for Kids - What is a Valley Glacier?

In mountainous regions, a river of ice may flow down a valley. This is called a valley glacier. 

A glacier can move at different speeds, from a few inches (centimeters) every year to as much as 660 feet (200 meters) every year.
Glaciers begin in small dips or hollows on mountainsides.
Every year more snow falls into these hollows than melts.
The weight of the snow eventually squeezes the air out of the bottom layers of the snow to form ice.
Where this ice meets the rock below, pressure generates energy to melt the ice.
The melted water on the rock surface seeps into tiny cracks in the rock.
The water then freezes and expands, forcing the cracks open, allowing more water to seep in and freeze. Finally, a piece of rock breaks off.
This process is called freeze-thaw.
In the hollow, the freeze-thaw causes more pieces of rock to break away, making the hollow bigger.
The hollow is now called a cirque.
When the layer of ice becomes very heavy, it starts to flow out of the hollow and down the valley.
It is now a glacier. 
As it moves downhill, the glacier picks up tons of sand, gravel and broken rock.
These materials are deposited along the way or pushed ahead of the glacier, forming uneven ridges called moraines.
Eventually, the glacier reaches the lowlands, where the air is warm enough for the ice to melt.

Ice Age for Kids - When was the last ice age - What caused the ice age

What is an ice age?

Have you ever tried to make a snowball?
Snow is soft and fluffy when it falls from the sky, but when you press it into a ball, it can become quite hard. If you press it very tightly, it turns into a lump of ice.
It is so cold at the North and South poles, that the snow there never has a chance to melt. As more snow falls, it presses down into tightly packed layers which then turn to ice.
Some areas of the earth are covered by huge sheets of ice and snow all year round.
Around the North Pole there is no land, but an ice sheet, also known as a continental glacier, covers the Arctic Ocean.
An ice sheet also covers most of Greenland and some northern parts of Canada and Europe.
The largest ice sheet in the world lies around the South Pole. It covers about 5.1 million square miles (13.2 million square kilometers) of the huge continent called Antarctica.
This ice sheet has an average thickness of 6,600 feet (2,000 meters).
The Antarctic ice contains about three-quarters of all the earth's fresh water.

For hundreds of years, many layers of ice have been forming in the Arctic and in Antarctica.
Scientists can now dig down into the ice to find traces of the past.
In Antarctica they have already found fossils of plant life, coal and other minerals.
Ice taken from deep down under the surface of Greenland shows that the air has been polluted with lead for hundreds of years.
Samples of ice also prove that lead pollution has become much worse during the past 100 years.
Scientists believe that most of this pollution is caused by the lead in gasoline.
The huge ice sheets around the North and South poles were once even bigger than they are now!
In the past, there were long periods of time when ice actually covered large areas of North America and northern Europe.
These periods of time are called ice ages.

When was the last Ice Age?

The most recent ice age began about 2 million years ago. The map shows which areas of
and is known as the Pleistocene Ice Age.

During each ice the world were covered with ice age, the ice advances and retreats several times. during the Pleistocene Ice Age.
In past ice ages, each advance of ice, or glaciation, lasted from 40,000 to 60,000 years.
In between glaciations there were interglacial periods of about 40,000 years, when the ice melted and retreated.

What causes Ice Ages?

Most scientists believe that ice ages are caused by a regular change in the shape of the earth's orbit around the sun.
This change seems to happen periodically, when the surface of the planet cools and huge ice sheets form. Since the last ice retreat began less than 20,000 years ago, we are now living in an interglacial period.
Some time in the future, the ice will advance again!

Electricity for Kids - What is a Transformer?

A transformer can make an electric current smaller or larger. As an electric current flows along the wires from a power station, it loses energy. A large current loses much more energy than a small current.
So power stations use transformers to reduce the current. Transformers do this by increasing the voltage. When the voltage is increased, the current becomes smaller. A transformer that increases the voltage is called a step-up transformer.
Many household appliances, such as radios and battery chargers, also use transformers. The voltage these appliances need is lower than the voltage of the electricity in your home. A transformer that reduces the voltage is called a step-down transformer.
Alternating current passes through the first coil in this step-up transformer. This makes an electric current flow in the second coil, which has more turns of wire. The voltage of the second coil is higher than the voltage of the first coil.

How do transformers work?

A transformer contains an iron core with two coils of wire wrapped around it. These two coils of wire have a different number of turns. Alternating current flows separately through each coil. In a step-up transformer, the second coil has more turns of wire than the first coil. The voltage of the second coil is then higher than the voltage of the first coil.
In a step-down transformer, the second coil has fewer turns of wire. The voltage of the second coil is then lower than the voltage of the first coil.

You can see a row of transformers at most power stations. At the top of each transformer there are round insulators. They prevent sparks of electricity from jumping between the high-voltage wires and causing a short circuit.

Electricity for Kids - What Does Voltage Mean?

You can make a bulb light up by using two wires to join it to a battery. 
The bulb lights up because an electric current is flowing through it. 
The battery produces the current by pushing electrons along the wires. 
The stronger the push, the more electrons flow along the wire each second. 
The current heats the thin wire inside the bulb and makes it glow brightly.

The force of this push is measured in volts. 

The word volts comes from the name of the Italian who invented the first battery—Alessandro Volta. 
The more volts a battery has, the stronger its push.
In a copper wire (A), some electrons move freely in all directions.
When a battery is connected to the wire (B), the battery pushes the electrons in the same direction.
An electric current can now flow along the wire.
When we do experiments with electricity, we use small batteries.
These batteries give a push of 1.5, 6.0, or 9.0 volts.
We describe this as the voltage of the battery.
This voltage is printed on the side of the battery.
The voltage of the power line to your home is much higher.
The voltage of the electricity flowing through the wires in most homes is at least 110 volts and may be as high as 220 or 240 volts.
A voltage of more than 100 volts is enough to push electrons through your body.
If a strong electric current passes through your body, the shock will hurt you badly and could easily kill you. So you must always use low-voltage batteries for your electrical experiments.

Electricity for Kids - What is Electric Wire?

Do you know how water gets to the faucets on your kitchen sink?
It comes through pipes.
Pipes let water flow in the direction we want it to go.
How do we make electricity flow in the direction we want it to go? 
The electrical energy we call "electricity" is made in huge power stations.
What connects the electric sockets in your home with the power station?
The answer is wires. 
Wires are the "pipes" of the electricity system.
A wire is a long, thin piece of metal. It may be a single strand of metal, or it may be two or more strands twisted together. Some wires are thick and stiff, and others are thin and bend easily.
Why are electric wires covered?
A material that allows electricity to flow through it is called a conductor. Metals are good conductors. Some metals are better conductors than others. Silver is the best conductor of all, but it is too expensive to use to make wires. Copper is also a very good conductor and much cheaper to use than silver. So most of the wires that we use to conduct electricity are copper wires.
But it's best not to try to conduct electricity along a bare wire. When a current is flowing through a bare wire, it will also flow through any metal object or other conductor that touches the wire. Even the human body can conduct electricity. If a person standing on the ground touches a bare wire which is connected to a power line, an electric current will flow through the person and into the ground. The person may receive a dangerous electric shock and might even be killed.
We need to make sure that electric current goes just where we want it and nowhere else. So the wires used to carry electricity are covered with materials that are poor conductors of electricity. Rubber and plastic conduct electricity poorly. They are both good insulators. A bare wire that is covered with rubber or plastic is called an insulated wire, or cable.

If cable is used for the circuit wires, there are three wires inside the cable. Two of these wires carry the electric current to and from the fuse box. One is a black, red, or blue wire and the other a white wire. The third wire, which can be bare or green, is called the ground wire. It may be connected to the main water pipe. If there is a fault in the wiring, the ground wire takes the current safely away into the ground.

Lasers for Kids - How Do Lasers Work

Did you know that light rays can cut through a steel plate? 

What sort of light can do this?
The answer is laser light.

A laser can produce a thin but very powerful beam of light.

Ordinary white light is made up of many different colors.
Its photons have many different wavelengths.
They are out of step with each other.
In a beam of laser light, all the photons have the same wavelength and move in step, traveling along like a well-drilled army.
A laser beam doesn't spread out like a beam of ordinary light.
Scientists have shone laser beams onto the moon, around 238,857 miles (384,403 kilometers) away. 
Over this huge distance, the beam spreads out by only 80 inches (2 meters) or less.
The laser beam's energy is concentrated into a narrow width and is very powerful.
Laser light can also be focused very accurately.
This is why lasers can cut steel and why surgeons can use laser light to perform very delicate operations. Laser light, which can pass through skin tissue, is focused on the part of the body which needs the operation. In eye surgery, for example, a retina that has become separated, or detached, from the back of the eye can be "welded" back into place using a laser beam.
Sometimes, dentists use a laser to remove decay from teeth.

Scattering of Light - Why does the sky look blue?

What color is the sky? 

On a sunny day, the sky looks blue. Sometimes, early in the morning and just before sunset, it may look greenish-yellow, or even orange-red.
The sky actually has no color at all. It is a great ocean of air, called the atmosphere, which is made up of colorless gases.
The sky looks colored to us because of what happens to the sunlight which passes through the atmosphere.
All kinds of particles, such as dust, smoke, and ash, float in the air. Many of these particles come from human activities, such as burning fuels to provide energy. Other particles are the result of natural happenings. Sometimes, strong winds whip up particles of desert sand. When volcanoes erupt, they send clouds of smoke and ash into the air.
When light strikes the tiny particles that are found in air and water, the light is scattered in all directions. When the sun is overhead and high in the sky, its light is scattered by the particles in the atmosphere. The light photons with the highest energy—violet and blue—are scattered more easily than those with a lower energy—red and orange. It is this scattered color that makes the sky appear to be blue.
At sunrise and sunset, we see the sun through a greater thickness of air because it is low in the sky. Therefore, we are looking at it across the earth's surface rather than directly up into the sky. At these times of day, the sky often turns an orange-red color. This is because the photons of red and orange light are scattered through the atmosphere around us.

As the sun is setting, its light travels to us across the earth's surface. The colors of the spectrum are gradually scattered. Red and orange are the last to be scattered before the sun finally sets.

First Moon Landing for Kids - What Year was the First Moon Landing?

The first moon landing

The most exciting thing astronauts have done so far is to travel to the moon.
They went in Apollo spacecraft, three astronauts at a time.
Each Apollo spacecraft was made in three parts.
The first part, the command module, carried the crew.
The second, the service module, carried equipment and a rocket motor.
The third, the lunar module, carried the astronauts down to the moon's surface.
The spacecraft was launched by the mighty Saturn V rocket, the tallest rocket there has ever been.
The journey to the moon took about three days.

The first astronauts landed on the moon on July 20,1969, 

They were Neil Armstrong and Edwin Aldrin, from Apollo 11. 

Armstrong was the first person to set foot on the moon. As he stepped onto the moon, he said,

"That's one small step for man, one giant leap for mankind."

Altogether, twelve astronauts from six Apollo spacecraft landed on the moon. They collected rocks, took photographs, and carried out experiments.
The astronauts also set up scientific stations, which radioed their results back to earth.
The stations carried on working long after the astronauts had returned to earth.

How to make a Telescope for Kids - Creative Activities for Children

Our eyes are good enough for simple stargazing.
But they tell us very little about what the stars are really like.

To see the stars more clearly and find out about them, we need to look through a telescope.

The word telescope means "see far," and that is just what a telescope enables us to do.

The Italian scientist, Galileo Galilee, was the first person to study the heavens through a telescope, in 1609.
Galileo made his telescope using glass lenses. Some astronomers still use this type of telescope today. It is called a refractor, because the lenses refract, or bend, light into the telescope. But the biggest and most powerful telescopes use mirrors to gather the starlight. They are called reflectors, because the mirrors reflect light into the telescope.

Up in the mountains

The places where astronomers work are called observatories. You find most observatories high up in the mountains. Here, the air is thin and clear, so the light can reach the telescope more easily. There is also less interference from the glare of city lights. At an observatory, the telescopes are kept in large buildings with dome-shaped roofs. Part of the dome slides back at night so that the telescope is uncovered. The dome swivels around so that it can point at any part of the sky. The world's biggest reflecting telescope, in the Soviet Union, has a mirror 20 feet (6 meters) across. It could detect the light of a candle 15,500 miles (25,000 kilometers) away!

How to make a Telescope at Home

Click to enlarge

Space Information for Kids - Planets in our Solar System

From the earth, we can see six of the other planets in our solar system without a telescope. They look like bright stars, but they change their position from night to night. This is why they are called planets. Planet means "wanderer."
The six planets are Mercury, Venus, Mars, Jupiter, Saturn, and Uranus. We can see them because they reflect the light of the sun—just as our moon does. The planet closest to us, Venus, is also the brightest. We see Venus sometimes at dawn as the "morning star" and sometimes at sunset as the "evening star." When they are closest to Earth, Mars and Jupiter shine nearly as brightly as Venus. Mars is easy to spot because it has a reddish-orange color. It is often called the Red Planet.

Mars and Venus appear so bright because they are our nearest neighbors among the planets. Jupiter lies very far away. It seems bright because it is so gigantic. It is more than a thousand times bigger than Earth! In fact, it is the biggest planet in the solar system.

What are planets made of?

Mars, Venus, and Mercury are balls of rock, like Earth. They are often called the terrestrial, or Earthlike, planets. The four giant planets—Jupiter, Saturn, Uranus, and Neptune— consist mainly of gas. These planets are similar in other ways. They are surrounded by rings made up of pieces of rock and ice. And they are at the center of miniature systems made up of many satellites, or moons.

The odd planet out is Pluto. This is the smallest planet of all, but it is so far away that we know little about it. It was not even discovered until 1930. It is a frozen world, with temperatures believed to be around -355 °F (-215 °C). Pluto has a moon called Charon.

Space Information for Kids - What is a Supernova?

Space Information for Kids - What is a Supernova?

Throughout the universe, there are great clouds of gas and dust.

These clouds are called nebulae. 

In larger nebulae, stars may form. The process begins when gravity pulls the gas and dust particles together.
As the mass of particles becomes tightly packed, or compressed, it heats up. In time, the temperature inside rises to about 2,000,000 °F (1,100,000 °C).
At such temperatures, atoms of hydrogen gas begin to combine, or fuse, together to form helium gas.
As they do so, they release an enormous amount of energy as light and heat.
The mass of gas and dust begins to shine—as a star.

...and dies.

A star the size of the sun has a long life. 

The sun is now about 4.6 billion years old and will probably stay as it is for another 5 billion years.
Then, scientists believe, it will run out of hydrogen "fuel" and begin to die.
First, it will swell in size and become a type of star we call a red giant.
Then it will slowly shrink again, becoming smaller and smaller, until it is not much bigger than the earth.
It will become a body called a white dwarf.
For their size, white dwarfs are very heavy.
A teaspoonful of material from a white dwarf weighs many tons!

What is a Supernova?

Big, heavy stars die spectacular deaths. They swell up into enormous super giants, many times their own size.
Then, they blast themselves apart in a mighty explosion called a supernova.
After a supernova, a tiny star sometimes remains.
It is called a neutron star, because it is made up of tiny particles called neutrons.
Very heavy stars do not form neutron stars.
They continue collapsing under gravity until they crush themselves into a very small space.
All that remains is a small area with an enormous gravity. This swallows up anything nearby, even light.

For this reason we call it a black hole.

Interesting Facts About the Sun

Interesting Facts About the Sun

Every morning the sun rises, bringing light and warmth to our world.
It is daytime.
The sun rises in the east, and during the day it appears to travel in an arc across the sky.
In the evening, it sets in the west.
As it disappears below the horizon, the earth becomes dark.
It is night.
However, this is not really what happens.
The sun only seems to move across the sky. It is the earth, not the sun,  that is moving.
The earth is spinning in space.
The sun moves into our view and out of sight again as the earth whirls around.

It takes the earth 24 hours to turn around an imaginary line that runs from the North Pole to the South Pole. We call this line the earth's axis.

Without the sun's light and heat, the earth would be a dark, cold world. 
Plants need sunlight to make their food.
Animals cannot make their own food. They must eat plants or other animals in order to live.

So without sunlight, there would be no living things.

What is the sun?

The sun is a star and is similar to the other stars in the sky. It appears bigger and brighter because it is much nearer than other stars.

The sun lies about 93 million miles (150 million kilometers) away.
The star nearest to us after the sun is over 25 million million miles (40 million million kilometers) away!

Heat from the sun warms the earth. The highest temperature recorded on earth was 136 °F (58 °C).

The temperature near the surface of the sun is 10,000 °F (5500 °C)!
At the sun's center, the temperature rises to about 27,000,000 °F (15,000,000 °C).

Sometimes we can see dark patches on the surface of the sun.
These are called sunspots.
We may also see arcs of gas called prominences or bursts of light called flares.
Prominences and flares are types of solar storms.
They usually happen above sunspots.

Scaling the sun

Atomic Mass Number - What is Atomic Mass Number?

Atomic Mass Number - What is Atomic Mass Number?

The total number of neutrons and protons in the nucleus (core) of an atom, makes the mass number of the atom (abbreviated A).
This number is an approximation of the mass of the atom.
Electrons contribute very little to the mass of the atom, so that they are not included in the mass number.
A stable helium atom may have a number of mass equal to three (two protons + one neutron) or equal to four (two protons and two neutrons).
The element Bismuth, which has 83 protons, requires 126 neutrons in order to be stable, so that its mass number is 209 (83 + 126 = 209).

Why do we Need Salt - Importance of Salt in Human Body

Why do we Need Salt - Importance of Salt in Human Body

The human body contains about 60 percent water. Many of our organs have an incredibly high percentage of water.
For example, the muscles are about 70 percent water, the same percentage of the liver, the brain  -  79%, and 83 percent the kidneys.
But the body fluid is not pure water.
This is actually a salt solution.
For what?
According to one scientific theory, all land animals, including man, descended from organisms that lived in the sea.
Bodily fluid of living creatures was seawater. When these creatures moved to the mainland, in their bodies remained sea water, but the land was not able to provide enough salt naturally.
Plants growing on the land does not contain enough salt.
Therefore, animals that feed on plants - herbivores - are in need of salt.

Why do we need salt?

The body of every-day loses a certain amount of liquid containing salt and plant foods do not compensate this.
However, animals that feed on the flesh - carnivores - do not feel such need for additional salt.
They are sufficient quantities of salt in the meat of their victims.
This is also true for humans. Eskimos, for example, eat mainly meat and therefore do not require any special intake of salt.

Residents of inland always look for more salt than those who inhabit the sea.
In Mexico, the salt was once upon a time considered so valuable that it even existed god salt.
And in Europe, in ancient times, human labor was paid with salt.
The salt of the human body accumulates mainly in the skin. If one person is on a diet food and does not take salt, the blood will lose salt through various ways of excretion. Then the skin must give the blood its reserves of salt, because salt concentration in the blood has to be constant. Assignment of salt reserves sometimes has beneficial effect in cases of some diseases.
Therefore, a diets that exclude salt are often recommended to ill people.
Salt is eliminated mainly trough kidneys.
If the kidneys develop a disease, patients are prohibited from taking salt to thereby reduce kidney function.

Why do People Sweat - What Causes Sweating?

Why do people sweat?

Let us imagine that our body is one perpetually lit stove.
The food that we take is the fuel that burns in our body.
During this process, the body takes about 2,500 calories.
This amount of heat is sufficient for 28.5 liters (7.5 gallons) of water to be heated to the boiling point.

What's going on with so much heat in our body?

If there was no temperature control, we'd probably be "hot."
But we know that our body temperature is 37 ° C (98.6F), except when we are sick.
Sweating is one way of ensuring the maintenance of normal body temperature.
If the temperature of the blood is increased, the center of the cooling comes into action.
The process of oxidation or burning substance slows down and something else that is important happens.
Blood vessels in the skin expand, and excess heat goes away trough the evaporation of perspiration. Therefore, for example, we feel cold after swimming, because the water that remains in contact with our warm skin evaporates quickly, and makes us colder.
Consequently, the sweating is part of the process of cooling the body.

Sweating is like a shower that washes the body. 

The liquid exits through a myriad of fine openings in the skin in the form of small droplets that evaporate quickly and rapidly cool the body - if necessary.
If in the air there is increased moisture, we will feel some difficulties because the water on our skin can’t easily evaporate.
Therefore, we are cooling ourselves with fan to "disperse" moist air and help the evaporation of sweat.

What Causes Aging and Can We Stop Aging?

Did you know that in ancient Rome ordinary man was expected to live up to 23 years?

About a hundred years ago the average life span was 40 years.

Most people would like to live a very long time, no one wants to get old.

But aging is a process that starts from birth and continues throughout the entire life.

What causes aging?

When someone enters a deepening age, all actions and processes of living organisms are slowed.
Man loses part of his strength and his senses lose sharpness.
It usually comes in the reduction of body weight and height.
Along with this, it may impair vision, partial deafness, white hair and relaxation and less supple skin.
Not all people are aging at the same speed, but some of the changes that come with age can not be avoided, because they occur in the tissues of the body and all its organs.
For example, cells in the kidney, liver, pancreas and spleen begin to gradually decline, because the blood vessels are old and not strong enough to supply blood and food, as in the past.
Thyroid and other glands also fail.
The entire system of blood circulation in the body with age begins to change and it is no longer functioning as active as used to.
Because of these changes, we do not even breathe the same way.
Eyes, ears, bones, joints, blood, skin, nails and teeth, it all starts to degenerate or deteriorate.
That is why older people often must change their lifestyle and diet.
These changes are biological and cannot be prevented, simply because aged tissues and organs can no longer operate at full power.
Age change is not the same everywhere.
A man of sixty years, can have some tissues and organs as a man of eighty years, while his other organs can be preserved as the man of forty, thirty, or even twenty years.

What are Hormones and What Do they Do?

What is a Hormone?

Hormones are secreted by the glands of internal secretion, which means that they are excreted in the body.
They are also called glands without drainage, because they do not send their products in the channels, but directly into the bloodstream.
Hormones also create some organs such as the liver and kidneys, but most of the hormones are product of the glands.

What do hormones do?

Each hormone has its own special function in the body.
In general, the task of hormones is to regulate internal body functions such as growth, nutrition esc., stockpiling of nutrients and their use, as well as the processes of reproduction. If glands produce too much or insufficient hormones, it can lead to abnormal physical appearance of the human.
Here's what some of the major glands and hormones work in our bodies.

Pituitary Gland Function

The pituitary gland is the most important of all, because it manages the work of all other glands of internal secretion. Its size is really surprising: this important gland is about as big as a pea, and nearly as much heavy. It was added to the lower surface of the brain and protected with one bone.
Although the pituitary gland is so small, it is divided into two clearly separate lobules - front and back.
Through the last lobule, which is smaller than the front, pass more than 50,000 nerve fibers.
Hormone produced in one part of the gland is tasked to encourage growth.
The pituitary gland produces two hormones that control utilization of water and fat, blood pressure and the way we regulate the heat in our body.
The pituitary gland controls and the development of sexual characteristics in both men and women. It manages and that part of the traffic of substances that has the task of turning food into different forms of energy.
The pituitary gland also affects the work of the muscles, kidneys and other organs.

Thyroid Gland Function

Thyroid gland, which is located in the neck, produces hormones that stimulate the growth and development of the body and metabolic processes in it.

Adrenal Gland Function

Above the top of both kidneys is one adrenal gland. It produces a hormone called adrenaline.
This hormone affects blood pressure response during agitation or unusual situations.
When a man is excited or frightened, it creates more of this hormone.
Other glands in the body produce hormones that influence human to behave like a boy or a girl.
As you can see, it depends from the hormones how you look and what is your health like.

What Causes Aging - When do People Stop Growing?

What Causes Aging?

When do People Stop Growing?

The newborn is on average 48-50 cm long.
Over the next twenty years, the body length is increased over three times and in a woman is about 160 cm and at males about 175 cm.
But the human then does not ceases to grow. It actually continues to grow, even after twenty-five years, and its highest altitude is reached in about 35 or 40 year.
What happens after these years? 
The man stops growing and starts to decrease. 
Everyone decreases after the age of forty, about 1 cm every ten years. Explanation for this decrease is the gradual loss of water from the cartilage in the joints of the spinal column.
Did you know that we are every morning higher than the previous night, and during the day we shorten?
The growth rate is also changed during the different seasons. Young children grow faster in summer than in winter.
Better food, better quality of life and a variety of other circumstances, make the today's generation, on average, higher than earlier ones.
Height growth depends on the work of four glands:
  • thyroid, 
  • pituitary, 
  • thymus and 
  • sexual. 
When these glands are working normally and there is an appropriate balance between their activities, growth is normal.
What Causes Aging - When do People Stop Growing

What causes aging - What is it that stops the growth?

The pituitary gland stimulates the bone growth. If this gland is over-working, hands and feet grow very large. If pituitary deficient work, the person remains a small in size - midget.
A child is born with a large thymus gland, which grows during childhood.
When the child is thirteen or fourteen years, the thymus gland is replaced by fat tissue.
At the end of the puberty in most people it is completely lost, and in its place remains fat tissue.
Such a reduction of the thymus gland falls at a time when sex glands begin to work.
A person who becomes sexually mature, which is later than the twenty-second year, ceases to grow.
 Sometimes the sex glands develop too quickly, and increase of the thymus gland slows down too soon. In such a case the person does not reach the average height. Since the legs grow later, but more than other parts of the body, in this early stage of development of the legs are short and people who prematurely develop often look dumpy.
Such, for example, looked Napoleon.
If the sex glands begin to develop late, thymus gland continues to work and such people reach above-average height.

How Do We Grow and What are the Stages of Human Development

How do we Grow?

One feature of the living things is growth.

By growth the living being improves its composition and functions.
The most important factors that cause growth are hereditary and can be found in embryo of the human being.

Different stages of human development

Human beings and animals go through several stages of development. These are:
  • embryonic stage (in the womb), 
  • period of the infant, 
  • childhood, 
  • adolescence, 
  • adulthood an
  • old age.
Some creatures barely have early childhood. Some birds, for example, can fly as soon as they hatch. Guinea pig is able to take care of itself, on the third day after the arrival in the world.
A human being is fully grown until approximately twenty years!
From the first moment the newborn has all those nerve cells that will have in a lifetime: the brain and the peripheral. Development of connections between these neurons allows the child to control his movements, to enter and act as a social being.
How Do We Grow and What are the Stages of Human Development

All human beings grow in a similar way, but there are some important differences between children of different sexes.
Boys and girls undergo the same path, but in different ways and at different speeds.
During the first few weeks after birth, the body is growing faster than ever later in life.
Already at the end of the first year it grows slowly, and throughout childhood quite moderate.
At the end of childhood, the growth rate starts to accelerate. This period in girls occurs usually between the eleventh and thirteen year, and in boys between twelve and fourteen. For a while they grow until they reach the maximum growth rate.
Then the growth rate begins to decline, until the moment when growth stops completely.
Growth in height and weight usually do not go at the same time.
First, human increase in height, and then we gain weight.

Backyard fun for kids - Animated Giraffe - Circus for Kids

The Giraffe is one of the rarest of animals, and very few are to be found in captivity. So if you make a giraffe, which is not difficult to do, you will have a feature in your show that none but the very largest combines can afford. The animal's head should be drawn the shape of Fig. 272 on a board, and then cut out with the aid of a saw and draw-knife. The jaw, ears, and horns should be cut out separately, the shape of Figs. 273, 274, and 275.
Bore two holes in the head at A, slanting them toward one another, and fit in them the pegs cut for the horns. The jaw should be pivoted with a small nail at B on one side of the head, and an ear should be likewise fastened at C on each side of the head. When these portions of the giraffe's anatomy have been put in place, stretch a rubber band from a tack driven in the top of the jaw to another tack driven into the neck (see Fig. 272), and attach another rubber band similarly to each of the ears. These rubber bands will act as springs, causing the ears to wag and the jaw to open and close when the giraffe moves his head.
Paint the head, making the features as nearly like those of a giraffe as possible, and, when the paint is dry, mount the head on the end of a six-foot pole.

Figs. 272-276.—Details of Giraffe.

The covering for the body is made out of a large piece of tan cloth with brown spots marked upon it, as shown in Fig. 276. It is not necessary to give a pattern for this, as the illustration clearly shows how it should fit over the two boys who form the body, and hang from the headpiece.

Fig. 277.—The Giraffe's Tail.
The neck should be stuffed out with excelsior. A short and a long stick should be nailed together, as shown in Fig. 277, and cloth should be sewed to the end of the short stick for the animal's tail. Stuff the tail with excelsior and fasten unravelled rope to the end, as shown in the drawings. The long stick should be held by the boy who forms the rear of the animal, so that by means of it he can manipulate the tail (see Fig. 276). As shown by the dotted lines in Fig. 276, the boy in the front portion of the animal holds the end of the pole supporting the animal's head.

Excerpt from the book - THE BOY CRAFTSMAN
Practical and Profitable Ideas for a Boy's Leisure Hours
BY A. Neely Hall
With more than four hundred illustrations by the author and Norman P. Hall
Published, August, 1905.

Fun activities for kids outside - Animated Elephant - Circus for Kids

The Elephant is one of the oldest forms of animated animals, and is at the same time one of the most popular. Four or five yards of gray cambric should be purchased for its covering.

Excerpt from the book - THE BOY CRAFTSMAN
Practical and Profitable Ideas for a Boy's Leisure Hours
BY A. Neely Hall / Published, August, 1905.
With more than four hundred illustrations by the author and Norman P. Hall

The cloth should be cut out like the pattern shown in Fig. 270, the correct measurements being secured from two boys who have taken the position shown in Fig. 271. Fold the cloth along the centre and then sew the dotted lines AA and BB together. Paper cornucopiæ form the tusks, and the ears are made of gray cambric cut the shape shown in Fig. 271, and lined with heavy wrapping-paper to make them stiff.

Two boys are required for the elephant. These must bend forward, as shown in Fig. 271. The rear boy places one hand upon the front boy's back and wags the tail with the other, while the front boy runs one hand through the elephant's trunk and keeps it in motion. Fasten potato sacks on to your legs to make them as large as possible.

Figs. 270-271.—The Elephant.

How to make Jump Standards

A Pair of Jump Standards are made out of two two-by-fours about eight feet long. After planing them smooth on all sides, measure off two feet from one end of each, and mark off the remaining six feet in inches, as shown in Fig. 259.

Excerpt from the book - THE BOY CRAFTSMAN
Practical and Profitable Ideas for a Boy's Leisure Hours
BY A. Neely Hall (Published, August, 1905.)

After squaring these divisions across the poles with your try-square, bore holes three-eighths of an inch in diameter through the poles at each division. Then, with a small brush and black paint, mark off each foot with a band extending around the pole, each half foot with a narrower band, and each inch with a short line, as shown in the drawings. Letter the foot divisions 1, 2, 3, 4, etc.

Figs. 259-262.—Details of Jump Standards.

When both standards have been finished, bury them in the ground to a depth of thirteen inches, eight feet apart. Cut two wooden pegs similar to Fig. 261 to fit the holes, and procure a nine-foot pine or hickory pole one inch thick for a cross-bar (see Fig. 260). When the bar is placed upon the pegs, the distance from its top to the ground should correspond with the figure on the upright. If not the same, raise or lower the uprights until the error is corrected.

With a pair of these standards there is no danger of injury by tripping over the bar, as the latter will fall off with the slightest knock. There is one disadvantage in using a stick, however, it being easily broken if jumped upon. Because of this, a rope with a weight attached to each end, as shown in Fig. 262 is often substituted. The ends of the rope are hung over the pegs in such a way that it will slip off the pegs when struck. The weights should be just heavy enough to prevent the rope from sagging in the centre.

Excerpt from the book - THE BOY CRAFTSMAN
Practical and Profitable Ideas for a Boy's Leisure Hours
BY A. Neely Hall
With more than four hundred illustrations by the author and Norman P. Hall
Published, August, 1905.

How to make Bow and Arrow and How to make Arrows for a Bow - Traditional Archery

Authorities claim that the best materials from which to make bows are mulberry, sassafras, Southern cedar, black locust, black walnut, apple, and slippery elm, in the order named; but if a boy selects what appears to be a good sound piece of wood, with straight grain, he has something which will suit the purpose.

Excerpt from the book - THE BOY CRAFTSMAN
Practical and Profitable Ideas for a Boy's Leisure Hours
BY A. Neely Hall
(Published, August, 1905.)

How to make Bow and ArrowFig. 241.—A Boy's Bow.

The Length of the Bow should be about the height of the person using it. Figure 241 shows a five-foot bow, with the other proportions such as are on makes to be found in the stores. Cut your piece of wood five feet long, and, after placing it in the bench-vise, shape it down with a draw-knife or plane until it is one inch wide by one-half inch thick at the handle and three-quarters of an inch wide by one-quarter inch thick at the ends. The bow can be made round on the inside or face toward the archer, and flat on the outside or face away from the archer, or the two faces may be made round. Cut a notch in the bow two inches from each end, as shown in the illustration, from which to attach

The Bow-string.

A cord with as little elasticity as possible should be used for this. If you care to spend the money for it, a good cotton string can be purchased from a dealer in archery goods for twenty-five cents. With a home-made bow-string, a loop should be made in one end and bound with thread, as shown in Fig. 242. Slip the loop over the upper notch, bend the bow until the centre of the string is about five inches away from the handle, and attach the loose end to the lower notch by means of a slip-knot similar to that shown in Fig. 243. The bow should be sand-papered until smooth, and thoroughly oiled with linseed-oil. A piece of velvet about three inches wide should be glued about the centre for a handle.

For a five-foot bow, cut

The Arrow-shafts twenty-four inches long and one-quarter inch thick. Whittle them out of straight-grained strips of wood, round them nicely, and cut a notch in the ends large enough to fit over the bow-strings.

It is not supposed that boys would care
Bow-string Ends.
Fig. 242-243. Bow-string Ends.

To Prepare Arrow-heads of stone or bone as the Indians did, for there are other schemes that are simpler to carry out. If the wood is reasonably hard, the heads can be cut on the ends of the shaft, as shown in Fig. 244. For target practice, a wire nail driven into the end of the shaft, as shown in Fig. 245, with the head of the nail filed off and pointed, has proven very good, and a thick piece of zinc or lead, cut the shape of A (Fig. 246) and set into a slot cut in the end of the shaft, with cord bound around the shaft to hold the metal in place, makes another excellent head. The metal points should be used only for target practice, and then with proper care, to prevent injury to yourself or companions.
How to make Arrows for a Bow
Figs. 244-246.—Schemes for Arrow-heads.

Feathering is the next operation. Turkey or goose feathers are generally used, but the former is considered the better of the two. Strip off the broader side of the vane of three feathers, and glue them to the shaft one and one-quarter inches from the notch, spacing them equidistant from one another. One feather should be placed at right angles to the notch. This is known as the cock-feather, and should always point away from the bow when the arrow is shot.

A Quiver of some sort should be provided, large enough to carry a dozen or more arrows, and this should be three inches shorter than the arrows, so that their ends will project above the top. It may be made out of any thick cloth, as shown in Fig. 247. A circular piece of cardboard is placed in the bottom to which the cloth is sewed, and a piece of heavy wire, bent into a circle, fits in the top to keep the bag open. The quiver should hang on your right side, being suspended by means of a cloth strap long enough to pass over the left shoulder.
A Quiver
Fig. 247.—A Quiver.

To Shoot with the bow, take the position shown in Fig. 248, with both feet flat upon the ground, and the heels in line with the target. Hold the handle of the bow in the left hand and place an arrow on the left side of the bow, slipping the bow-string into the notch and letting the head of the arrow rest upon your left hand. Catch the bow-string with the first three fingers of your right hand, so that the end of the arrow comes between the first and second fingers, and draw the string until the head of the arrow rests upon the left hand; then aim quickly and let go of the arrow. By always taking the same hold upon your bow and arrow, you will soon be able to know just where the arrow is going to strike.

The boy who has had the hobby of collecting Indian arrow-heads has no doubt often wondered how they were made, and also how the bows and arrows were prepared. The ways in which all uncivilized people do things is interesting, and especially when it is remembered that they had but raw materials with which to work and only such tools as they could make out of stone.
Correct Position for Shooting
Fig. 248.—Correct Position for Shooting.

The Indian's Bow was made of different woods, and, though it varied in shape and size, was generally about forty inches in length, so as to be conveniently carried and handled on horseback. The bow-string consisted generally of a deer sinew or a strand of deer-skin rolled or twisted, and this was strung very tightly from a notch cut on one end of the bow to a notch on the opposite end. Now, while an Indian generally made the greater part of his weapons, there was always a warrior in the tribe who was skilled in the art of arrow-making, and, as the preparation required far more care than the bow, he was intrusted with this work. The arrow-shaft was made of various woods, reeds being often used, as they were straight and required but little cutting. Their lengths depended largely upon that of the bows.

For the feathering of the shafts, wild turkey feathers were considered best and used when they could be had, and these were attached to the shaft with deer sinews.

A great variety of materials were used for arrow-heads, among which flint, obsidian, horn of deer, claws of eagles, and the spurs of wild turkey-cocks may be mentioned. Many of these are being picked up annually in the mountains and on the plains, which were once the battle-fields and hunting-grounds of the redmen, and in excavating for building purposes they are frequently found. A few specimens of stone heads showing a variety of the shapes and sizes used will be found in Fig. 249. The preparation of these heads was usually left to the old men who were unfit for any other work.

Some Specimens of Indian Arrow-heads 
Fig. 249.—Some Specimens of Indian Arrow-heads.

In making the flint head, the Indian made a loop in a piece of buckskin which had been thoroughly wet in cold water, and then taking a piece of flint, heated it, and with the strip of buckskin chipped off what was not wanted until the head was of the correct shape and size. As hornstone is more brittle than quartz, the heads made from that material were broken and shaped by striking them against the latter. The stone heads were attached to the shaft by means of sinews, generally from deer. For hunting small birds, the Indians often made wooden arrow-heads, hardening the wood by fire after shaping it.

Excerpt from the book - THE BOY CRAFTSMAN
Practical and Profitable Ideas for a Boy's Leisure Hours
BY A. Neely Hall
With more than four hundred illustrations by the author and Norman P. Hall
Published, August, 1905.

How to Build a Canoe - Wood and Canvas Canoe

How to Build a Canoe - Wood and Canvas Canoe

Canoeing is a most delightful outdoor sport, and one of the healthiest in which a boy can indulge during his vacation days. Its popularity can plainly be seen by visiting any lake or stream, and noting what a large percentage of the small craft dotting its surface are canoes of various shapes and sizes, paddled by boys of all ages.

Excerpt from the book - THE BOY CRAFTSMAN (Published, August, 1905.)
Practical and Profitable Ideas for a Boy's Leisure Hours
BY A. Neely Hall

For speed and the ease with which it can be carried about, the birch-bark canoe has no equal, but very few boys own them, as they are expensive, and their construction is more difficult than those of other material which will satisfy a boy fully as well.

The canvas canoe is more widely used at the present time than any other form, which is no doubt due to the fact that it is very simple to make and keep in repair, and the cost of its material is small.

In building a canvas canoe there are two important things to consider,—its weight and strength. These depend upon the material used. The framework must be made stiff enough to hold its shape, as the canvas adds but little to its strength, and at the same time the wood should be as light as possible. There are a great variety of

Materials from which to choose for building the framework, among which basswood, ash, spruce, and pine may be classed. The canoe described and illustrated in this chapter may have its ribs, ribbands, and gunwales made out of lattice-strips and barrel-hoops, which will save the cost of having them cut to the right size at a mill. Pine or fir lattice-strips of good sound stuff are generally easy to obtain in all locations.

1 piece of 2-inch by 8-inch plank 6 feet long for bow and stern pieces.
15 2-inch by ⅜-inch lattice strips 12 feet long for ribbands, gunwales, keel, and bilge-keels.
20 barrel-hoops for ribs and deck braces.
1 strip 8 feet long, 2 inches wide, and 1 inch thick for keelson.
2 strips 4 feet long, 2 inches wide, and ⅝-inch thick for deck ridge pieces.
2 strips 8 feet long, 4 inches wide, and ¼-inch thick for cockpit frame and coaming.
Several 6-inch and 8-inch boards from which to cut deck beams, patterns, etc.

Copper nails and brass screws should be purchased for fastening the framework together, and copper tacks for putting on the canvas. Iron nails will rust and break off, and therefore should not be used in any part of the canoe's construction. Use nails only where their ends can be clinched, and screws in all cases where this cannot be done. For covering the framework, three and one-half yards of canvas forty inches wide will be required for the lower portion, and the same amount thirty inches wide will be required for the deck. Boiled linseed-oil should be purchased for filling the canvas and the best grade of mixed paint for painting it. A drab, or cream color and white trimmings, are both suitable for a canoe. If the latter is used, buy white paint, and, after pouring out enough to cover the finishing strips, mix the rest with enough yellow ochre to make a pretty shade of cream.

Below will be found a bill of the material required to build a canoe such as this chapter describes, and although the prices of canvas and a few of the fittings are likely to fluctuate somewhat, the price of the canoe should not exceed this amount, and there are locations where it may be less.

BILL OF MATERIAL (!!! in 1905   !!!)
3-½ yards No. 10 Duck, 30 inches wide, 27 cents    $0.95
3-½ yards No. 10 Duck, 40 inches wide, 36 cents    1.26
1-½ pounds 1-inch Copper Nails, 30 cents    .45
2 pounds ⅜-inch Copper Tacks, 35 cents    .70
2 dozen ¾-inch Brass Screws (Flat Heads), 7 cents    .14
6 dozen ⅝-inch Brass Screws (Flat Heads), 6 cents    .36
3 dozen ⅝-inch Brass Screws (Round Heads), 6 cents    .18
½ gallon Boiled Linseed-oil    .25
½ gallon Best Quality Mixed Paint    .75
15 Lattice-strips, 12 feet long    .90
1 Piece of 2-inch by 8-inch Plank 6 feet long    .20
Miscellaneous Strips and Pieces (see page 202)    .50
Total cost    $6.64 (!!! in 1905   !!!)

Having procured the necessary material for the canoe, the first things to make are

The Bow and Stern Pieces

The proper way of laying these out on the eight-inch plank is shown in Fig. 201. First cut the plank in half, and then place these two pieces side by side upon the floor or work-bench as shown in the drawing one piece upon which to draw the pattern, and the other upon which to locate the centre for drawing the curves.

Fig. 200.—Bow and Stern Pieces.
Then square the line AB across the planks, and locate the points D and E on either side of it, by means of the measurements given upon the drawing. The most satisfactory scheme for

Fig 201
Then with a ruler lay off along the line AB the distances for the other arcs, as shown in the drawing. FG will be two inches from DE, HI an inch and one-half from FG, and JK an inch and one-quarter from HI. Having located these points and described the arcs, draw the lines CD and CE, extending them so as to cut off the arcs, as in the drawing. At the upper end of the pattern draw the line LM one inch from and parallel to FD. With a radius of an inch and three-quarters and the centre N describe an arc as shown in the drawing. At the lower end of the pattern draw the line OP two inches from and parallel to GK, and the line QR one inch from and parallel to PK. Having carefully drawn out this pattern, turn over the plank and draw the same thing upon it, locating the points exactly opposite one another, by squaring lines across the sides and edge. Prepare the other piece of plank similarly. To cut out the patterns, place them in the vise of your work-bench, one at a time, and rabbet the surfaces between DE and FG, and FG and HI, as shown in the section drawing, Fig. 202. This done reverse the piece and do the same to that side. When these surfaces have been trued up carefully, remove the piece from the vise and saw the pattern from it. In doing this, first saw along the lines DJ and EK, and cut out the corners FLMD and PQRK. Then follow roughly the curves of lines DE and JP, after which place the work in the vise and trim them off nicely with a draw-knife, rounding the outer curve as shown in Fig. 202. The portion OQRG should be cut down to a plain surface as shown in Fig. 200.
Fig. 202.—Section through Bow and Stern Pieces.

With the bow and stern pieces completed, the most difficult part of your work has been accomplished.

Now pick out the eight-foot strip procured for

The Keelson.

Square off the ends so that it is exactly eight feet long, and then, commencing six inches from one end, lay off mortises for the ribs (see Fig. 203). These mortises should be cut half an inch deep and the width of the barrel-hoops, and their centers should be spaced twelve inches apart.

Fig. 203.—The Keelson.

In order to give the correct shape to the canoe in putting the framework together, it will be necessary to make
A Mould similar to Fig. 204. Fasten together two boards about two feet long with battens, as shown in the drawing, and with a piece of cord to which a pencil has been attached describe a semicircle upon it, using a radius of eleven and one-half inches. Saw out the mould carefully, and in the center of the bottom cut a mortise two inches by one-half for the keelson to fit in.

Fig. 204.—The Mould.

Everything should now be in readiness

To put the Framework together.

In order to give the keelson the proper slope of one inch between its center and ends, nail two blocks of wood one inch thick to the work-bench eight feet apart, and rest the ends of the keelson upon them. Then fasten the ends of the keelson in the mortises cut in the bottom of the bow and stern pieces. Set the mould which you have prepared over the exact center of the keelson, and fasten it in place temporarily. When this has been done take two lattice-strips for

The Gunwales, and after locating the exact center of each, screw them at this point to the ends of the mould just below the top. Drive these screws but part way in, as the mould is to be removed later on. Commencing at the bow end of the canoe, draw the end of one gunwale to the bow piece, and, after marking it the correct length cut it off so it will fit nicely in the rabbet cut in the side of the bow piece. Then screw the other end to the stern piece, after which attach the gunwale on the opposite side in the same way (see Figs. 200, 205, and 206).

Now take the barrel-hoops which are to be used for ribs, and fasten them in the mortises cut for them in the keelson, bending their ends until they come inside of the gunwales. Then fasten them to the gunwales and trim their ends so as to be even with the top of the canoe (see Figs. 205 and 206).
Fig. 205.—Top View of Canoe, showing Gunwales, Ribs, and Ribbands in place.
Fig. 206.—Side View of Canoe, showing Framework completed.
Fig. 207.—Top View of Canoe, showing Framework completed.

After fastening the ribs in place,
The Ribbands should be put on. Pick out eight of the soundest lattice-strips you have, and fasten these at their centre to the sides of the mould, placing four on each side of the keelson and spacing them at equal distances. As the mould is only temporary, do not fasten the ribbands to it securely, but drive in the nails part way.

Then, beginning at the bow, draw the ends of the ribbands to the bow piece one at a time, and cut them off so they will fit neatly into the rabbet. Screw them in place, being careful to space them as equally as possible, after which attach the stern ends in the same way. Figure 205 shows the top view of the canoe at this stage of its construction.
The Deck Beams should now be made and put in place, one each side of the cockpit, or fourteen inches from the centre of the canoe (see Fig. 207). At this point measure the exact distance between the gunwales, and lay it off upon a four-inch board (see Fig. 208). The top of this piece should be curved as shown in the drawing, and a mortise two inches wide by five-eighths of an inch deep should be cut in the edge for the deck ridge pieces to fit in. As a means of preventing the gunwales from spreading, it is best to dovetail the ends of the deck beams into them (see Fig. 207). Cut a tongue half an inch long and half an inch thick on each end of the beams, as shown in Fig. 209, undercutting it slightly, as in the drawing, to make it wedge-shaped. Then, having prepared the ends, place the beams in the positions they will occupy in the framework, and mark upon the top of the gunwales the shape of the tongues. Mortise the gunwales at these points (Fig. 210), so the tongues can be slipped into them and fastened in place. By examining the corners of a drawer you will see clearly how the dovetail joint is made.

The Ridge Pieces are strips running from the deck beams to the bow and stern pieces (see Figs. 206 and 207). For this canoe, they should be made out of a strip two inches wide by five-eighths of an inch thick. Cut them of correct length to reach from the mortises in the tops of the deck beams to the mortises cut in the tops of the bow and stern pieces. Mortises two inches wide and a quarter inch deep should be cut along the top of these ridges, as shown in Fig. 211, to receive the deck braces. Securely screw the ridges in place. Then cut twelve pieces of barrel-hoops for

The Deck Braces, and fit them in the mortises made in the ridge pieces. Screw these in place and bend their ends until they can be fastened to the inside face of the gunwales. The curve of these braces should be the same as that of the deck beams, so it will be possible to put on the deck canvas neatly (see Figs. 206 and 207).

The space between the deck beams is left for

The Cockpit, the frame for which we are now ready to prepare. First remove the mould, being careful that the framework does not spread in doing so. Then cut two two-inch strips to fit between the deck beams, and fasten one on each side of the cockpit two inches from the gunwale (see Fig. 207). When this has been done take the strip eight feet long, four inches wide, and one-quarter inch thick, procured for the cockpit frame, and bend it around the opening, fastening it to the sides of the deck beams and the side strips. The top edge of the frame should now be shaved off with a draw-knife, so that it will be on a line with the deck braces at every point (see Fig. 206). This is necessary in order to make the curve of the deck around the cockpit the same as elsewhere.

The framework of the canoe is now completed, and should be painted and left to dry before you go on with the rest of the work.

It is no easy matter to stretch

The Canvas Covering over the framework without having it wrinkle, but with the help of a boy friend it can be stretched fairly even, and with care and patience may be made to look neat.

Turn the framework bottom side up and, after finding the centre of the forty-inch strip of canvas, lay it along the keelson from bow to stern. Smooth it over the surface with your hands, and start a few tacks along the keelson to hold it in place. As a means of keeping the canvas stretched over the bottom of the framework while working upon it, attach several weights to the edges; then, with your helper on the side opposite you, commence at the middle rib and stretch the canvas down that rib to the gunwales, starting a couple of tacks in the gunwales to hold it in place. Then work along each rib from the centre of the framework toward the bow, and then from the centre toward the stern, stretching the canvas as tightly as possible, and driving tacks along the gunwales not farther than one inch apart. You will find that the only way to get the canvas on smoothly is by removing the tacks wherever any wrinkles appear and, after restretching it, replacing the tacks. As the tacks will probably have to be removed a number of times during the operation, it is advisable to drive them in but a little way at first.

It is most difficult to make a neat job at the bow and stern, and a few wrinkles will probably remain, no matter how much pains are taken in fitting the canvas, on account of the narrowing of the canoe at these points. Fill the outer mortise made in the bow and stern pieces with paint, and, after folding the edges of the canvas, tack it in these mortises. Place the tacks as close as their heads will permit, which, together with the paint, will make a joint that water cannot penetrate. Now examine the canoe carefully, and, if you have smoothed out the wrinkles as much as possible, drive home the tacks and trim the canvas close to the gunwales.

The Deck is much easier to cover. Spread the piece of thirty-inch canvas over it from bow to stern, with the centre of the canvas running along the centre of the deck, and place a tack in it at the bow and another at the stern. Stretch the canvas in the same manner as when covering the bottom of the framework, and lap it over the gunwales, tacking it along the outer edge. Cut through the canvas at the cockpit, and trim it off so there will be just enough to lap around the cockpit frame. Trim the canvas along the gunwales so that it does not project more than an inch.

After the deck has been covered, the canoe is ready for


A coat of linseed-oil should first be applied to the canvas, to fill the pores and make a good foundation for the paint. Then allow the canvas to dry thoroughly, after which give it a coat of paint,—cream, or whatever color you have selected. When this has dried, rub it down with pumice-stone or fine emery-paper, and apply a second coat.

All that now remains to complete the canoe is the attachment of the cockpit coaming, the keel, bilge-keels, and the outside gunwales. Take the strip eight feet long, four inches wide, and one-quarter inch thick, which you procured for

The Cockpit Coaming, bend it around the frame of the pit, and cut off the ends so they will join neatly. Then fasten it to the cockpit frame, allowing two inches to project above the deck, and shave off the top edge the same as you did the cockpit frame, so it will be two inches above the deck at every point.

For a small canoe built for paddling only, it is unnecessary to have anything more than a strip fastened to the bottom for

The Keel.

So cut a lattice-strip eight feet in length, and screw it along the bottom of the keelson (see Fig. 212).

The Bilge-keels are lattice-strips fastened along the sides of the canoe as a protection to the canvas, and should be attached directly over the ribbands. One of these on the centre ribband of each side will be sufficient (see Fig. 212).
 Fig. 212.—The Canvas Canoe completed.

For a finish to the upper edge of the canoe,

Outside Gunwales should be attached outside of the present ones. These will cover the joint between the canvas of the deck and the lower portion of the framework. All of these outside strips should be fastened in place with the round-headed screws, after which they should be painted. Figure 212 shows the canoe completed.

A Seat is desirable for the bottom of the canoe, for comfort as well as to prevent your feet from wearing out the canvas. This seat should be movable, so it may be taken out to drain the water from the bottom of the canoe, and may be made as shown in Fig. 213. Batten together two six-inch boards upon their under face and notch the two side edges to fit over the ribs of the framework (see Fig. 207).

Fig. 213.—Seat.

In order to keep your canoe in good condition, do not allow it to remain in the water for any length of time when not using it, as the canvas would soon rot by doing so. After a spin, pull it out of the water, and turn it upside down to dry; then put it away under cover to remain until again wanted for use.

With the greatest of care a boy will puncture his canoe once in a while, so it is a good idea for him to know

How to mend Punctures.

There are several ways of doing this, but the best is by either sewing a piece of canvas over the puncture and then painting it with white lead, or daubing the canvas around the hole with varnish, and then laying a canvas patch over it and varnishing it.

The making of a well-shaped paddle is no easy matter for an amateur to accomplish, so it is advisable for a boy to procure

A Hand-made Single Paddle, such as can be bought for a dollar and a half. This is generally made of selected spruce, with a copper-tipped end, and is nicely finished. The length of the paddle will depend upon the size of the boy who is going to use it, but should be between four feet six inches and five feet.

It may be well to warn those who build canvas canoes about the ease with which they are overturned. As long as the boy remains seated he is perfectly safe, but the moment he attempts to change his position, he need not be surprised if he receives a ducking. Upsets are common in canoe-racing, and especially in a close finish, where one paddler after another overbalances himself in his efforts to beat out his companions. But these only add to the fun of such a race, and no harm is done if the canoeist prepares for them beforehand by putting on his bathing suit.

Excerpt from the book - THE BOY CRAFTSMAN
Practical and Profitable Ideas for a Boy's Leisure Hours
BY A. Neely Hall
With more than four hundred illustrations by the author and Norman P. Hall
Published, August, 1905.