The Microwave Oven

Shortly after the end of World War II, Percy Spencer, already known as an electronics and war hero, was touring one of his laboratories at the Raytheon Company. He stopped momentarily in front of a magnetron, the power tube that drives a radar set. Feeling a sudden and strange sensation, Spencer noticed that the chocolate bar in his pocket had begun to melt. Spencer, who obtained 120 patents in his lifetime, knew how to apply his curiosity. So he did what any good inventor would he went for some popcorn. Spencer didn't feel like having a snack, he asked for unpopped popcorn. Holding the bag of corn next to the magnetron, Spencer watched as the kernels exploded into white morsels.

From this simple experiment, Spencer and Raytheon developed the microwave oven. The first microwave oven weighed a hefty 750 pounds and stood five feet, six inches. At first, it was used exclusively in restaurants, railroad cars and ocean liners - places where large quantities of food had to be cooked quickly. But culinary experts quickly noticed the oven's shortcomings. Meat refused to brown. French fries turned white

and limp. To make matters worse, Raytheon chairman Charles Adams cook quit because Adams demanded he prepare food with a microwave oven. In fact, it took decades after the invention of the microwave oven for it to be refined to a point where it would be useful to the average consumer. Today, Percy Spencer's radar boxes melt chocolate and popcorn in millions of homes around the world.(1261)

Ice Cream Cone

For folks who lived anywhere near St. Louis, Missouri, the biggest event in the summer of 1904 was the Louisiana Purchase Exposition, which took place in that city. No one knew beforehand, but that exposition was the occasion where ice cream cones were first made and sold. The person who did it was named Charles Menches and he was a seller of ice cream. But he didn't plan to invent the ice cream cone. This is how it happened. Charles Menches sold his ice cream in dishes the way every other ice cream man did. That August when the Louisiana Purchase Exposition was at its height, was a real scorcher, however, and one day disaster struck Mr. Menches. There were so many hot and thirsty fairgoers wanting ice cream that he ran out of dishes. And it wasn't even noon. He had more than half a

day of business ahead of him and not a single dish to serve his ice cream on. What did Menches do? He looked around him and thought fast. Nearby was a stand where his friend, Ernest Hamwi, who was from Syria, was selling a Middle Eastern treat called Zalabia. Zalabia consists of a crisp, wafer-like pastry sold with syrup. "Give me Zalabia!" cried Menches. He rolled up the Zalabia, scooped his ice cream on top, and presto! Ice cream corne were born(1030)

Machines in Space

The earth is one of several satellites of the sun. Satellites are things that go around the sun or a planet at the same speed all the time. The earth's biggest satellite is the moon, but since

1957. when Russia launched the first man-made satellite, there have been hundreds of others sent up to do different jobs.

There are different kinds of man-made satellites in space. Military satellites have cameras which can see what is happening in other countries. These help countries defend themselves against surprise attacks. Communication machines, called Comsats, travel through space at the same speed that the earth turns so that they are always over the same place. Signals from one earth station are received and sent back down to another station thousands of miles from the first. Before Comsats, it was necessary to lay long expensive cables, which couldn't carry many messages. Comsats carry thousands of messages each minute.

Map makers are drawing much more accurate charts and maps because they have photos from survey satellites showing exactly where everything is, and weather forecasters have photos of all the clouds around the world. They can see when a storm is forming, and they can tell how long it will take to strike. Navigators on ships and airplanes can now find out exactly where they are by use of the Satnav system - even when it is cloudy or foggy and no stars are to be seen.

Laboratory satellites are usually the only ones that have people in them. The Russians have a lab that has been constantly occupied by scientists for many years. There are plans to build a very large satellite called a space station. Much of the knowledge about how to do this has been learned aboard American Shuttle labs which become satellites for a few days at a time and then return to the earth, so the labs can be changed and sent into space again to learn something

Someday, people may live their entire lives aboard satellites in space.(1627)

Apollo Astronauts. Land on the Moon.

The start of America's effort to get humans to the moon is often linked to President Kennedy's 1961 speech, which set this as a goal to achieve by the end of the decade. His speech boosted funding for NASA [National Aeronautics and Space Administration), but the journey to the moon really goes back to 1959, when NASA was just beginning.

NASA’s first space exploration program, named Mercury, was an urgent attempt 16 catch up to the Russians, who had already launched an orbiting satellite and put a dog into space. Mercury successfully put an American into earth orbit in 1961 for 24 hours. The next stage of the U.S. space program, called Gemini, advanced spacecraft design by engineering dockable components. The Apollo program followed, named for the Greek god of music, prophecy, medicine, light, and progress.

Apollo spacecraft were designed for travel to the moon. Improving on Gemini's component parts, Apollo spacecraft were made up of three modules. The command module could carry three astronauts. The service module held the engines, electric power generator, and oxygen and water stores.

The lunar module was itself a two-stage vehicle, designed to get the astronauts from the command module orbiting the moon to the moon's surface, and then to serve as their shelter while on the moon. Several test flights were accomplished, but on January 27, 1967 a fire in the command module on the launch pad killed all three drew members. A faulty hatch had prevented their escape. NASA took a step back from its hurried pace. The missions of Apollos 7, 8, 9, and 10 tested equipment in Earth and lunar orbit, but Apollo 11 was slated to land on the moon. It launched on Julyl6, 1969 at 9: 23 a.m.

Seventy-six hours later, it entered lunar orbit. There was a television camera on board the lunar module, so the entire world could see mission commander Neil Armstrong climb lightly dawn the ladder in the moon’s low gravity and could hear his slightly scratchy voice transmitted to Houston: ’’That’s one small step for a man; one giant leap for mankind.”(1741)

SPACE AGE BEGAN

SPACE AGE BEGAN October 4, 1957, the world awoke to a new sound. A very weak "beep " coming from outer space. People everywhere tuned their radios to listen to the first man-made artificial earth satellite - Sputnik. The Soviet Union had beaten the United States to space.

It was 500 miles up, traveling at 18,000 miles an hour; and it circled the globe every 96 minutes and it flew over the United States seven times a day. The sound of its incessant beeping fascinated and disturbed the nation.

FIRST MAN IN SPACE

The Space Age began or October 4, 1957, when the Soviet Union launched the first Earth-orbiting satellite -Sputnik. It

weighed 184 pounds (83.6 kilograms). The highest extent of its orbit was 584 miles (942 kilometers). It circled the Earth every 96 minutes and remained in orbit until early 1958, when it fell back into the atmosphere and burned.

The effect of Sputnik on an unsuspecting world was electrifying. The United States was especially surprised and embarrassed. The public's attention was immediately directed to the failure of the schools to teach mathematics and science adequately. Although this failure was not fully remedied, the United Stales did put its first satellite into orbit on January 31, 1958. The space race had begun.

Just as the Soviet Union beat the United States into space with Sputnik in 1957, so it was first to send an astronaut into space in 1961. The Soviet cosmonaut's name was Yuri Gagarin, who graduated from the Air Force school at Orenburg in 1958. Gagarin went aloft in the spaceship Vostok 1 on April 12,1961, at 9:07 a.m. He orbited the Earth once in one hour and 29 minutes, reaching a maximum altitude of 187 miles (301 kilometers). The ship landed the same day at 10:55 a.m. It was Gagarin's only space flight.(1481)

First Electronic Computer

The first fully automatic large-scale calculator was built by Howard Aiken of Harvard University working with engineers from International Business Machines Corporation. It was called Harvard Mark I and was completed in 1944. Data were entered on punched cards, and output was on punched cards or processed on an electric typewriter. It was a large machine - 15 meters long and 2.4 meters high.

The first generation of what can be called a real computer, not just a calculator, was the Colossus, put in operation in 1943 in Bletchley Park, near London, England. It was used to decipher German codes in World War II The Colossusi however, was built only for this task. The distinction of the first general-purpose computer goes to a machine known as ENIAC - Electronic Numerical Integrator and Calculator - designed and built by J. Presper Eckert and John W. Mauchly of the University of Pennsylvania in 1946.

These Machines were enormous by today's standards, but they were less powerful than today's computers. They used hundreds of vacuum tubes. The invention in 1948 of the more efficient and much smaller transistor which does the same work as vacuum tube, helped make today's personal computers possible.(1034

Personal Computer

In 1974, calculators were the hot item in consumer electronics. A little calculator company in Albuquerque was struggling to compete, but a price war threatened to bankrupt it. Its owner, research engineer Ed Roberts, determined to make it all or nothing. He decided to build a small computer based on the recently developed, inexpensive microprocessors from Intel, and sell it to electronics hobbyist at the amazingly low price of about $500. Roberts called his computer the Altair 8800 and offered it as a kit.

The Altair didn't actually do much as a computer. It didn't have a screen or a keyboard or any software. But it filled a hole. It was the very first personal computer on the market. The larger computer companies were busy developing mainframes and improving computer systems for industry, and couldn't really see why anyone would want a home computer. They also failed to see the implications of the new microprocessors that were small and cheap.

Users had to program Altair in machine code using toggle switches. A Harvard student and his friend, Bill Gates and Paul Allen, realized Altair would be a lot better if users could program it in BASIC, a popular, easy-to-use computer language, instead of machine code.

The enterprising pair called Roberts offered to develop a BASIC interpreter for the Altair. He agreed and within six weeks bought the program from Gates and Allen. He hired Allen as software developer. Allen and Gates later established Microsoft Corporation.

Altair sparked an entire industry, as new personal computer companies popped up in its wake. One of these companies was the creation of a hobbyist who couldn't afford an Altair kit, so he created his own from scratch. Stephen Wozniak polished up his creation in 1976. With his friend Steve Jobs, he began to sell it and then improve it. In 1977, they introduced Apple II and made Apple Computer Company the fastest growing business in American history.

In 1977 Ed Roberts sold his company. Two years later, like many others entering the volatile market, it had folded. In 1982, IBM entered the fray with its own personal computer, the PC, which became Apple's biggest competitor.(1823)

Computer Mouse:

First Introduction

Years before personal computers and deskpot information processing became commonplace or even practicable, Douglas Engelbart had invented a number of interactive, user-friendly information access systems that we take for granted today: the computer mouse was one of his inventions. At the Fall Joint Computer Conference in San Francisco in 1968, Engelbart astonished his colleagues by demonstrating the before mentioned systems using an utterly primitive 192-kilobyte mainframe computer located 25 miles away! Engelbart has earned nearly two dozen patents, the most memorable being perhaps for his "X-Y Position Indicator for a Display System": the prototype of the computer "mouse" whose convenience has revolutionized personal computing.(667)

Who discovered penicillin?

Penicillin was the first antibiotic, a special drug that is very good at killing bacteria. With antibiotics, many illnesses can soon be cured that were once incurable. Penicillin was discovered by accident by the British scientist Sir Alexander Fleming in 1928. He noticed that a mold which had formed in a dish in his laboratory was killing bacteria in the dish. From the mold, penicillin was later prepared. In 1938, Howard Floery and Ernst Chain found a way to make penicillin in large quantities.

Alexander Fleming returned to his research laboratory at St. Mary’s Hospital in London after World War I. His battlefront experience had shown him how serious a killer bacteria could

be, much worse even than enemy artillery. He wanted to find a chemical that could stop bacterial infection.

He discovered lysozome, an enzyme occurring in many body fluids, such as tears. It had a natural antibacterial effect, but not against the strongest infectious agents. He kept looking. Fleming had so much going on in his lab that it was often in a jungle. This disorder proved very fortunate. In 1928, he was straightening up a pile of Petri dishes where he has been growing bacteria, but which had been piled in the sink. He opened each one and examined it before tossing it into the cleaning solution. One made him stop and say, “That’s funny.”

Some mold was growing in one of the dishes. ...not too unusual, but all around the mold, the staph bacteria had been killed ... very unusual. He took a sample of the mold. He found that it was from the penicillium family, later specified as Penicillium notalum. Fleming presented his findings in 1929, but they raised little interest. He published a report on penicillin and its potential uses in the British Journal of Experimental Pathology.(1504)