Where do sponges come from?

The bath sponge we use in our home is the soft skeleton of an animal that once lived in the sea.

Probably many sponges you see at home were made in a factory.  They are made of synthetic material to look and clean like true sponges.

If you have ever used a true sponge to wash anything, you are using the soft skeleton of an animal that once lived in the sea.

Sponges don’t look like other animals.  A sponge has no head or mouth.

Water flowing through the many holes in its body brings oxygen and tiny bits of plant matter that provide food for it.

For almost all its life, the sponge stays in one place—attached to the ocean floor.

There are sponges of all shapes, sizes and colors.  Some are shaped like fans, vases, and bowls.

Some sponges are only about as big as a pea.  Others may grow to be several feet tall.

Sponge fishermen use a long, hooked pole to pull up sponges that live in shallow water.  In deep water, fishermen dive for sponges in diving suits. – Dick Rogers

What Makes A Boomerang Return?

Boomerang

The boomerang’s shape, together with its spinning motion through the air, makes it return.

A boomerang is a curved throwing stick used by the natives of Australia and some other countries as a weapon or for hunting.  There are two kinds of boomerangs—the return and the nonreturn boomerang.

The return boomerang has the ability to return after a curving, spinning flight, and land at the feet of its thrower.

Such boomerangs consist of curved, hardwood blades which are usually flat on one side and slightly rounded on the other.  The ends are slightly twisted in opposite directions.

It is this shape, together with the spinning motion of the boomerang as it whirls through their, that makes it return to you.

Some people think that the boomerang comes back after hitting its target.  But this is not true.  The first part of the boomerang’s path is nearly straight.  It is expected to hit its target while in this part of its flight, and return only if it misses the goal.

The nonreturn boomerang is heavier and is nearly straight, and does not return to the thrower.  It is used mainly or hunting or as a weapon. – Dick Rogers

What Is Hominy?

Hominy

Hominy is a food made by soaking corn kernels in a lye solution to remove the hull.

Hominy is a kind of food made from hulled Indian corn.  Hominy gets its name from an American Indian word for “parched corn.”  It has been a favorite food in the South since pioneer days.

Corn was one of the important foods of a pioneer family because it kept well in any season.  Young, ripe corn was eaten as roasting ears.  In winter corn was often prepared and eaten as hominy.

To make hominy, the dried corn was husked and the kernels soaked in a weak lye solution to remove the tough skin, or hull, of the kernel.  After the kernels were washed, they were ready to be cooked.

Hominy was usually boiled in water and was usually served with meat.  For breakfast and supper, hominy was often ground up as “grits” and boiled in milk or water and eaten as a cornmeal mush.  Sometimes the mush was fried and served with butter or pork drippings.-Dick Rogers

What Are Air Plants?

Air Plant

Air plants are plants that grow on other plants for support and get their water and food from the air.  Many ferns, mosses and orchids are air plants.

Some plants spend their entire lives perches high in trees.  These  plants are called air plants.  Another name for them is epiphytes (pronounced EP ih fites), a name that means “upon plants.”

Many orchids and ferns are air plants.  Spanish moss, which hangs in long, gray festoons from tree branches, is a well-known air plants of the southern United States. Unlike mistletoe, a plant that steals its food from the plant it grows on, the air plant does not take any food from its host.  The only help it needs from the host plant is to be lifted up into the sunshine.

It gets nourishment by taking water directly from the air and from decayed matter which collects on the plant or on the bark of the tree. Some air plants have long, spongy air roots that dangle in the moist air and soak up the water they need.  Others take in moisture from the air through their leaves or stems.-Dick Rogers

How Does A Camera Take Pictures?

Camera

Camera film is coated with special chemical sensitive to light.  A camera is basically a box which light cannot enter, except through a small hole located at one end of the camera.

This opening is covered with a glass lens.  A shutter opens and closes the hole behind the lens.  When we open  and close the shutter of the camera quickly, light enters through the lens.

The lens throws a picture of what is in front of the camera onto the film inside.  The film is coated with a chemical sensitive to light.  When a picture is flashed onto the film, a chemical change takes place, and an invisible picture is formed on the film.

Later, at the camera shop, the film is developed in special solutions to make the film picture visible.  This film picture is called a “negative.”  The photographer uses the negative to make the photograph we see. Moving picture cameras work much like other cameras.  They simply take one picture after another very rapidly.– Dick Rogers

Where Does Dust Come From?

Dust

Housekeepers spend a good deal of time dusting.  Dust settles from the air and makes a gray coating over everything around us.  

Dust is more that just specks of dirt.  In the ordinary dust you could collect from a windowsill, you would find tiny chips of rock, bits of dead wood and dried leaves.  

Dust may also have in it spores from plants, pollen from the powder in flowers, spot from smoke, cinders left from meteors burning up on their way to earth, and other bits of matter that float in the air.  Dust may drift hundreds of miles before finally setting because of gravity.-Dick Rogers

What is brass made of?

Brass

Brass is a yellowish metal made by melting copper and zinc together.  Brass is hard and strong and holds a bright finish. Many of the metal things we use today are made of brass.

Brass is a long wearing, yellowish-colored metal that is used in making such familiar things as brass doorknobs, pins and brass musical instruments.  It has a great many other important uses as well.

But no one has ever heard of brass mines.  That’s because there are not any.  Brass is not a single metal, as is gold or iron.  It is a mixture of two metals – copper and zinc.  A mixture of this kind is called an alloy.

In making brass, the copper is melted in an electric furnace.  Small pieces of solid zinc are then added to the melted copper.  The zinc dissolves in the motion copper in much the same way salt may be dissolved in water.

When the mixture cools, it hardens into a metal that is much stronger and tougher than pure copper, and therefore resists wear better.  Brass can be polished to a bright finish.-Dick Rogers

Who invented San Francisco’s cable cars?

Cable Car

Andrew S. Hallidie invented the cable car in 1873.  They run on rails and are pulled by an endless steel cable.

Cable cars are a popular way of traveling up and down the hilly streets of San Francisco, California.

Cable cars were invented in 1873 by Andrew S. Hallidie, an American manufacturer of wire cables.  At that time, most American cities had horse-drawn buses.  But the streets of San Francisco were too steep for horses to climb with heavy loads.

Hallidie placed an endless steel cable in a slot under the street.  Large underground motion turned wheels that pulled the cable along the slot.  A car could be moved by means of a grip which extended down through the slot to the moving cable.

When the grip man pulled back on a lever the grip seized the cable and the car was pulled along on steel tracks.  These little cars still rattle over the crest of Nob Hill and other streets as a reminder at earlier times.-Dick Rogers

What is St. Elmo’s Fire?

St. Elmo's Fire

St. Elmo’s Fire is the flash of light that is seen around ships in a thunder storm.  It is an electrical discharge caused by the storm.

St. Elmo’s Fire is the name sailors have given to the sudden glow of ghostly flames that can sometimes be men flickering around ships in stormy weather.

The “fire” is actually a charge of electricity that builds up in the ship as it sails along in the storm.

When enough electricity has built up, the ship discharges its electrical overload into the air in a flesh of light that looks like fire as it fizzes and crackles around the tall masts.

This kind of electricity isn’t strong enough to hurt you – but it may make your fingers tingle.

“St. Elmo” is the nickname of Saint Erasmus, guardian saint of Mediterranean sailors.  They once believe that St. Elmo’s fire was a sign that he was watching over their ships and protecting them during storms.

Sometimes you can see St. Elmo’s Fire on land during thunderstorms, flickering from tail church steeples and treetops. -Dick Rogers

How are subway trains powered?

Subway Train

A subway is an electric railroad that runs under the ground.  Subways provide quick and cheap transportation in many big cities and help keep the streets free from traffic.

Subway trains are made up of several cars that look very much like railroad cars.  Each car may hold 100 or more passengers.

Subway trains run on tracks and are powered by an electrically charged third rail placed beside the track.  The electricity is picked up by a special metal device called a “shoe” that slides along this rail.

The electricity powers the motors that drive the train’s wheels.  A motorman in the lead car starts and stops the train at the stations along the route.   

Stairs and escalators lead from the subway station to the street above and trains below.  In England, subways are called “tubes.”  In some other countries they are known as “metros.”-Dick Rogers

Who invented barbed wire?

Barbed Wire

Barbed wire was invented by an American, Joseph F. Gidden, who patented it in 1874.

If you have over visited the countryside where livestock is raised, you probably know what barbed wire is.

Barbed wire is a cable of twisted wire armed with barbs of sharp points.  It is used particularly as an economic means of fencing off large areas.

It provided an inexpensive substitute for wood fences and enabled small farmers to fence in homesteads and settle communities on the western frontier.

Barbed wire is made by feeding two strands of wire, side-by-side, into the wire making machine.  Other wires used to make the barbs are run crosswise over the strand wires.  

At regular space intervals the machine cuts a length from them and twists the barbs around one or both strand wires.  After this is done, the strand wires are twisted together to form the finished cable.  It is then rolled to shipment to dealers.-Dick Rogers

Why is Japan called the Land of the Rising Sun?

Japan

Japan got its nickname from an ancient myth that the island of Japan were the source of the rising sun.  Japan, the island country in the Pacific Ocean, is often called the “land of the rising sun.”

It is believed that Japan got its nickname from ancient Oriental folk beliefs that the islands of Japan were the source of the sun.

Long ago, the people of ancient China watched the morning sun rising from the eastern sea, they wrote down stories of gods and warriors that lived on sacred island hidden in the ocean.

The Chinese called the islands “jih pun” (today we say “Japan” instead), which literally means “source of the sun.”  As for the Japanese, old regards claimed that Japan was founded by the Sun Goddess who, along with other gods of nature, made the island her home.

And that is the story of how Japan came to be looked on as the “land of the rising sun.”  Japan’s official name is Nihon, or Nippon which in Japanese also means “source of the sun.” – Dick Rogers

Why are marines called leathernecks?

Leathernecks

United States marines got their nickname “leathernecks.”  They got this nickname because, in the early days, they wore black leather neckbands on their uniforms, presumably to protect their necks against enemy sabers and cutlasses.

The Marine Corps is the branch of the armed forces specially trained for duty aboard warships as well as on land.  The use of marines does far back in history.  

The first seagoing spiders called on King Solomon’s galleys nearly 3,000 years ago.  And sea spiders served on the warships of Egyptians and ancient Greeks.  The United States Marine Corps was first organized in 1775 to help defend the American colonies during the American Revolution.

Today many countries, including the United States and Great Britain have marines.  The traditional nickname for British marine is “bootneck,” probably stemming from the same origins the word “leathernecks.” – Dick Rogers

When did ballet dancing begin?

Ballerina

Ballet is a special kind of dancing in which the dancers perform gracefully leaps and glides and often dances on their toes.

Ballet as we see it today had its beginnings in the royal courts of Italy nearly 500 years ago.  It developed as a kind of entertainment from the steps of the elegant court dances of the day.

However, there were no toe slippers such as a ballerina wears today.  And dancing of this kind was not called “ballet” until almost 100 years later.

Over the years many people have added new steps and improvement to the ballet.  The ballet often tells a story, but there is no singing or speaking.  The story is told by the movements of the dancers.

The dancing is done to music and is combined with beautiful costumes and scenery to entertain the audience. Ballet is not easy to learn.  It takes years of careful training and a great deal of practice to become a good ballet dancer.-Dick Rogers

Why do we need parking meters?

Parking Meter

Parking meters are used mainly as a means of getting an efficient turnover of parking spaces in crowded city business districts.

While motorists shop they must have parking space.  A big problem for most cities is the lack of sufficient curb parking spaces for the large number of vehicles that enter the business district each day.

As a way of getting an efficient turnover at parking spaces, parking meters are often used.  A parking meter regulates the length of time a vehicle may park in a particular parking space.

A parking meter is a kind of time clock.  When anyone parks a car in a metered space, he has to put some money into the parking meter.  The time clock inside it is set in motion by the coin.

When the time on the meter is used up, a red flag appears on the meter.  If the car is with there after the meter turns off, a policemen can issue a violation ticket for over-parking.  The first city in which parking meters were ever installed is said to be Oklahoma City.  The Year:  1935. – Dick Rogers

When did libraries begin?

Library

Libraries began thousands of years ago as archives in which records, maps and other important documents were kept.

The word “library” comes from the Latin word “liber” which means “book.”  There have been libraries almost as long as there have been books.

The first real libraries we know of existed thousands of years ago in ancient Mesopotamia and Egypt.  The “books’ in these early librarians did not look at all like ours.  They were written by hand on tablets of clay and on long rolls of papyrus (a paper-like material) and were kept in temples and palaces.

The first public libraries were built in ancient Greece more that 2,000 years ago, but they were only open to scholars.  They were the only people who could read books.  During medieval times books written by hand on parchment paper were so precious that they were often  chained to the shelves.

As libraries developed over the centuries, they grew from small collections available to only a few scholars to large public libraries open to everyone.-Dick Rogers

How did museums start?

Museum

Museum as we know them today grew out of the private collections started by wealthy people during the middle ages.

Where could you go to see an Egyptian mummy or the paintings of great artists?  Where could you see the bones of dinosaur?  The answer is “a museum.”

Just you may collect stamps or coins, museums are places that collect and display valuable art works, stuffed animals and many other interesting historical and scientific objects.

The first museums were founded in ancient Egypt.  They were usually places where art, music and the sciences were studied.  Museums as we know them did not develop until many centuries later.

They grew out of the private collections of works of art and other treasures started by wealthy people during the Middle Ages.  Today there are many different kinds of museums to visit.  Art museums, for example, collect and show paintings, statues and other masterpieces of art.

And you can see model dinosaurs in museums of natural history.-Dick Rogers

How does a siren work?

Siren

A siren is a kind of whistle which makes a loud noise as air is blown through holes in a spinning cylinder or disk.  It is a wailing noise

When a fire truck roars through the streets, its loud siren warms people to get out of the way.  An ordinary air siren has two cylinders, one inside the other.  The cylinder contain a number of holes.

When the fireman presses the button, an electric motor spins the inner cylinder and air is pushed through the holes.

When the holes in the inner cylinder are lined up with the holes in the outer cylinder, puffs of air escape and cause vibrations.  When the vibrating air (sound waves) reach our ears,  you hear the familiar ooooooOOOOOOEEEEEEeeeeee noise of the siren.

The faster the inner cylinder spins, the greater number of puffs of air, and the louder the siren.  A newer kind of siren makes its wailing sound electronically.  It does not have a moving parts like the older types. – Dick Rogers

What is parchment?

Parchment

Parchment is the dried skin of goats, sheep or other animals, treated so that it can be written on.

If you had lived long ago, in medieval days, you might have read books whose pages were made of animal skins instead of paper.

The first books made of pages bound together in a cover were made of parchment.  This is a king of material made from the skin of goats, sheep, and other animals.

Because parchment is expensive to make, the parchment on which a book was written was often considered more valuable than its content.  Frequently the ink was erased so that the parchment could be reused.

By the 1500s, paper had replaced parchment for all but the most formal documents.  The important-looking paper on which the diploma you get when you graduate from school is usually printed is called “parchment paper.”

Parchment paper is a kind of paper that is treated to look almost like real parchment, it lasts fro many years, but it is not as expensive as parchment.-Dick Rogers

How is nylon made?

Nylon

Nylon is a product of a chemical process in which carbon, nitrogen, oxygen and hydrogen are united to form a strong, tough material.

Nylon is a strong, long-lasting synthetic material.  Its uses range from such things as shear hosiery and fishing lines to toothbrush bristles and molded parts for machinery.

Nylon is made from common elements obtained from coal (carbon) and air (oxygen and nitrogen) and water (hydrogen).  These elements are heated, mixed and treated to such a way that they are changed into a substance called “nylon salt.”  

The nylon salt becomes a thick, gooey liquid when it is heated.  The melted nylon is spread out into a thin sheet to cool.  When hard, the sheet is cut into chips.  The chips are then melted and manufactured into final products.

To make yarn for weaving stockings and fabrics for clothes, the melted nylon is pushed through time notes in a metal plate.  Several threads of nylon are then twisted together into a single yarn and then stretched to make the nylon strong.–Dick Rogers

What is a doctorate degree?

Doctorate Degree

A doctorate degree is the highest degree awarded to a person by a college or university.

In the United States, a student who graduates after four years of study in a college or university normally receives a “bachelor’s degree” and usually specializes in a field of study called his major subject.

Some students begin work in their new professions after earning a bachelor’s degree.

Many do not stop their studies at this point, but go on for graduate studies that lead to a highest master’s degree, and then to a doctor’s degree to practice in special professions such as medicine, dentistry, law, or the field of education.

Degrees are awarded (conferred) at a ceremony called “commencement” – a term that means the beginning of a career outside academic surroundings.  A person on whom a college or university has conferred the doctorate is properly addressed as Doctor (abbreviated “Dr.”).–Dick Rogers

What is the difference between a lake and a pond?

Lake

Generally, a pond is described as a small body of still water without an outlet.  Lakes are usually much larger and deeper and often are fed by rivers and streams.  Generally, lakes differ from ponds in size.

A lake is commonly descried as a large body of water with land all around it.

A pond is usually smaller than a lake.  It is a quiet pool of water so shallow that rooted plants often grow completely across it and the bottom is usually covered with mud.

The cool water in a lake is often too deep for plants to grow except around the shore.  What people know as a pond or a lake, however, may differ from one place to another.

Pond

In some places, for example, a pond may be called a marsh.  And some large bodies of water commonly known as seas are really lakes, such as the Caspian Sea and the Dead Sea.

The “bowl” that holds a lake or pond is called the basin.  The basins of ponds and lakes may get their water from rain or be filled with water that flows into them from rivers, streams, or sometimes even from underground springs.–Dick Rogers

What makes a railroad crossing signal go on?

Train crossing signals are worked automatically by electricity made to flow when the train’s wheels touch certain sets of rails near the crossing.  People walking or riding need to be warned at an approaching train when they are about to cross the tacks on the highway.

Railroad Crossing Signal

Safety gates may close.  Electrically operated waving arms and flashing red sights accompanied by the ringing of a crossing bell can also warn of an approaching train.

When you see a train speeding down the track, you may wonder how the signals know it is coming.

The safety signals are operated automatically by an electric current that flows through special sets of rails near the crossing.  When the train’s  metal wheels touch the rails, they close the electric circuit. Causing the safety gate to close, the red lights to flash and the crossing bell to ring.

When the train is safety through the railroad crossing the wheels touch a second set of electrified rails on the other side, which turn the signals off and open the safety gate for the traffic.–Dick Rogers

What is the biggest desert?

Sahara Desert

The Sahara desert of North Africa is the Largest desert in the world.  It is nearly as big as the whole united states.

Almost as large as the whole United States, the Sahara stretches across the northern part of Africa from the Atlantic Ocean to the Red Sea.  

The Sahara desert is a vast, sun baked land of flat, rocky plains, shifting sands and rocky uplands.  A burning sun and scorching winds make it the hottest region in the world.  On summer days, the temperature may research 130 degrees F.  

Scattered through the Sahara there are oases, places where a spring or well provides enough water for date palms and other crops.  Only one river, the Nile, runs across the desert.  

The Sahara people wear long robes and turbans wound around the head and neck for protection against the hot sun and stinging sandstorms.  Camels were once the only means of transport across the Sahara.  Nowadays, buses and trucks cross many of the Sahara’s routes.–Dick Rogers

What do we mean by Latin America?

Latin America

We often use the name “Latin America” when speaking of countries located South of the United States.  It  comes from the fact that these countries were settled largely by the Spanish and Portuguese, and  as a result, have many of the Latin Cultural traditions.

The term includes Mexico, Central America, South America, and most of the West Indies.

The name Latin America comes from the fact that almost Portuguese and French settlers who spoke languages that grew out of Latin – spoken by the ancient Romans.

As a result, most people speak one of those languages.  Their religion, arts and customs came largely from these southern European countries.

Because of this “Latin culture,” the people are often called Latin Americans and the countries in which they lie are collectively called Latin America.

Not all people like to use the term “Latin America.” Other names that are sometimes used include Spanish America, Indo-America and Ibero-America.–Dick Rogers

What Is Oil Shale?

Oil Shale

Oil shale is a kind of rock that contains kerogen, a waxy substance that gives off liquid when heated.  Not all oil comes from oil wells that bring oil up from underground pools.

Much of the world’s supply of oil is  found in a kind of rocks formed of tightly packed clay, mud and slit.  This rocks is called oil shale.

Actually, this shale does not contain oil. It contains “kerogen” a  waxy material which, when heated, gives off a liquid  oil.

To get the oil from the kerogen  in the oil shale, the shale “ore” is mined and crushed.  Then  it is heated  in a furnace called  a retort. One  ton  of oil  shale  may  yield from  10  to 50- or-more gallons  of  crude oil.

When it  has been  refined, the oil can be separated  into gasoline and  other petroleum products, just as oil from  oil  from oil wells  is separated.

Shale oil is not widely used because it  is expensive to make.  But as the world ‘s supply of oil diminishes, oil shale may someday provide an important source of oil for all of our machinery.–Dick Rogers

Why do we say A.M. and P.M. when telling time?

The  letters A.M (ante meridian) P.M (post meridian) tell us  what part of the day it is on a 12 hour clock. 

As we all know, there are 24 hours in a day but only 12 hour numbers on a clock.  This is because in  most  countries the hours of the day are usually divided into two parts  for  timekeeping..

We call the  first  part  of the day  a.m. the second part p.m.

The  first clued clocks did  not keep  good time.  They had to be set every  day at noon, when the  sun  was at the  meridian, or the  highest point in the sky.

From  this we began to call the morning  part of the day a.m., meaning ”ante meridian.” or before noon.  P.M. means “post meridian” or after noon.

If every  town set its  clocks  by the sun today, few  places would  be on  the  same time.  When it is noon  in  one town, it is not yet noon in a town a few miles east.  For this reason. the world is divided into time zones.   All the clocks in a time zone are set  the same time.-Dick Rogers

How Do Hearing Aids Work?

Modern hearing aids work much like miniature telephones.  They  have microphones to pick up sound and  amplifiers that increase the loudness in the ear  of the wearer.

Perhaps  the hearing of  someone  you know is not as good as it was when  he was  younger and he must now wear  a hearing aid.

Hearing Aid

A  hearing aid is a sound  amplifier -  a device that increases the loudness of  sounds in the ear of the wearer.

The earliest  hearing   aid  was the ear  trumpet. This was  a  trumpet- shaped  instrument.  Its small end was  placed  to the ear. It simply  gathered in sound and funneled  it into the ear.  Today people who are hard-of hearing use  small transistor hearing aids instead of ear trumpets.

Modern hearing  aids are  essentially  small battery-powered  telephones.  They have  microphones to pick up sound and amplifiers to make sounds  louder.

A  button- sized  receiver fits in the ear or behind it, depending on the  type of hearing defect, and sends sound  vibrations to the hearing center.  Sometimes, hearing aids are so  tiny  that you hardly notice them.–Dick Rogers

Who invented the piano?

Piano

The piano was invented  early  in  the 18th century by an  Italian harpsichord maker  named Bartolommeo Cristofori.  The piano is a stringed  instrument played  with a keyboard. 

The first piano was invented  early in the 18^th century by an Italian harpsichord maker named  Bartolommeo  Cristofori.  His invention  was designed to remedy  the harpsichord’s inability to play softly or loudly by the touch of the fingers. 

He called  his invention “gravicembalo  col piano  e  forte”(Italian  words meaning “harpsichord  with soft and  loud”) to show that, unlike the  harpsichord, it could be played both loud and soft with ease.  The name was shortened  to piano- forte and finally to piano.  The keyboard of a standard piano consists of 88 white and black keys.

Inside the piano  there are many wire strings stretched over a sounding board.  There are also wooden  hammer  covered  with  felt.  When  you  push down on a piano key, a hammer  strikers a set of strings.  The strings vibrate and  make the musical sound.–Dick Rogers