This edited article about the gramophone originally appeared in Look and Learn issue number 704 published on 12 July 1975.

A child in the ‘Sixties playig  LPs on a stereo record player

“Is it a British or a German submarine? We must be able to hear the difference!”

This was the awesome task set by R.A.F. Coastal Command when they approached the Decca gramophone company during World War II. It was a secret assignment and called for a record to be produced which could be used as a training aid to familiarise airmen with the subtle differences made by the sounds of the enemy and our own submarines.

Difficult as the problem was, Decca came up with the answer – a record with such a wide range of sensitive sound that it was completely satisfactory.

Intensive research had produced an exciting new recording technique, stretching the gramophone’s capabilities to a greater extent than ever before. Adapted later for musical reproduction after the war’s end, the process became known as “ffrr” (full frequency range recording,) and Decca took it as their trademark.

It was not long after the war, that another kind of battle began, this time between the rival recording companies.

In 1948, Columbia Records of America held a Press Conference in New York to launch a revolutionary idea, invented by Dr. Peter Goldmark, called the LP (Long Playing) record. Their new 12-inch disc turned out to be made of non-breakable vinyl plastic, played at 33 and a third r.p.m. on microgrooves and lasted 23 minutes per side. It had about 250 grooves to the inch instead of about 80 in the 78 r.p.m. record.

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This edited article about Donald Campbell originally appeared in Look and Learn issue number 682 published on 8 February 1975.

Donald Campbell and Bluebird

Donald Campbell leaned in the boathouse against Bluebird, the powerful jet-engined boat on which he was about to challenge the water speed record.

His chief mechanic, Leo Villa, found him there, gazing at Coniston Water in Lancashire, his thoughts miles away.

“Morning, skipper,” said Leo. “The lake doesn’t look at all bad today.”

“Oh, hello, Unc.,” said Donald. “You’d better get everybody out to their stations.”

To Villa, Campbell seemed unusually curt, for he was usually ready for a chat. But Villa did as he was bid, and in a few minutes the scene was set for the battle of a man and his machine against the forces of nature.

Clearly, Campbell was not happy. While playing cards the night before, he had drawn the ace and queen of spades. He said to the members of his team of mechanics who were playing with him, “Mary Queen of Scots drew the same two cards the night before she was beheaded. I have the most awful premonition that I’m going to get the chop this time.”

Although Campbell could have called off the attempt, he did not, for the days when the weather was right and the boat was in good shape were too rare during those winter months of 1966-67. And, in any case, there was always an inner compulsion driving him on.

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This edited article about aviation originally appeared in Look and Learn issue number 681 published on 1 February 1975.

Various aerial aircraft carriers including the Stratofortress and its rocket-powered aircraft (bottom right corner), by Ray Calloway

The pilot of the little Grebe plane revved up his engine. It spluttered like a motor bike and then burst into a full-throated roar.

For a second, the pilot glanced up at the huge airship that had brought his plane to its present altitude. Then he gave a thumb’s up sign to the men in the airship’s cabin and opened his throttle wide. What would happen now? Never before had an airship been used as an aerial aircraft carrier and nobody knew if it would be a successful idea.

In a second, the pilot had his answer. His plane dropped a hundred feet, falling madly out of control. Fortunately, the pilot kept cool, regained mastery of his aircraft and flew it safely back to its base.

This was in 1926 and, although this experiment was a success, the idea of using airships to carry planes to a future enemy was abandoned in the same year. But, it was continued with larger planes carrying smaller ones on their back or slung beneath a wing. The idea was to carry a smaller plane, with its limited fuel capacity, to its operational area. It was also used to get small planes with heavy loads into the air and to take rocket planes to a high altitude.

The latter method was adopted by the Americans to carry out speed tests on their rocket-powered research aircraft. These were launched like a bomb from beneath the wing of a huge Stratofortress. They shot away to attain a height of 354,200 feet and a speed of 4,250 miles an hour. One of these achieved the first supersonic flight in 1947 and another became the world’s fastest fixed-wing aircraft at 4,520 miles an hour.

This edited article about aviation originally appeared in Look and Learn issue number 680 published on 25 January 1975.

Various historic and modern planes with different kinds of swept wings culminating in Concorde (bottom right) by Wilf Hardy

Ever since the Wright brothers conquered gravity with a heavier-than-air machine in 1903, men have been seeking ways of building better and faster aircraft. It is a far cry from the historic, chain-driven plane, in which Orville Wright flew for 12 seconds, more than seventy years ago, to the mighty jets of today. But the intervening years have been marked by many achievements which have brought aircraft to their present peak of perfection.

One of the most remarkable of these has been the introduction of swept wings. Early aircraft either had single or double layers of wings (biplanes or monoplanes) and while these created buoyancy they also limited the speed at which the plane could fly.

With the development of more powerful engines, the need arose for aircraft to be designed which could remain stable at very high speeds.

The swept wing was the answer to this. Sweepback, as the design is termed, minimises the effects of the shock waves that build up when an aircraft reaches the speed of sound.

Swept-back wings had been experimented with as far back as 1930, as can be seen from the shape of the Granger Archaeopteryx. During the Second World War, the Miles’ Dragonflies had swept wings or, to be more specific, a swept tail which was called a tandem wing.

Since the war, most high speed aircraft have been built with swept-back wings, and greater and greater speeds have been attained. Airliners which fly at over 600 miles an hour and bombers which whine through the heavens at twice the speed of sound are part of today’s aviation scene. Swept-back wings, allied to the aircraft’s overall design and the power of its engines, have made this achievement possible.

This edited article about water originally appeared in Look and Learn issue number 678 published on 11 January 1975.

The Cabora-Bassa Dam  built on the mighty Zambesi in Portuguese Mozambique, which is guarded by armed patrols (inset)

Scientists as far back as the time of Alexander the Great in Egypt, realised the potentialities of water. They formulated the theory that moving mass has energy and water has mass, therefore this element could be used for useful purposes.

In such a barren country as Egypt, irrigation was obviously the first priority. The chief method of irrigation was the swape. This is simply a boom pivoted to the top of a post. A bucket hangs from the long end with the short end held down by a counterweight. One man handles the weight while the other empties the bucket each time it rises into the trough to save the man scrambling up and down the river bank.

Other wheel-shaped devices were designed for transferring water. One is called the tympanum or drum. This had spaces around the outside to let the water in, the inside being divided by spiral partitions. As the tympanum turns, the water in each section is raised until it runs out of the hole in the hub.

The Greeks were also interested in putting water to work. Archimedes, the Greek scientist, invented what became known as the Archimedean Screw.

This is a tube with a screw-shaped partition running its length. When it is in the water and turned, water is trapped in each screw and forced through to irrigate parts that the water would not normally reach.

It is a far cry from such a primitive effort to the modern dams in Africa where water is channelled to make electricity.

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This edited article about radio astronomy originally appeared in Look and Learn issue number 677 published on 4 January 1975.

Jodrell Bank

A cacophony of crackles, buzzes and hisses filled the ears of Karl Jansky, an American engineer. The headphones he was wearing almost jumped and jived to the variety of sounds that came from them. But Jansky was unperturbed. He sat in his shack, filled with radio equipment, listening to the noises and noting their types.

Jansky had been employed by the Bell Telephone Laboratories to find a way of combating the electrical interference that was spoiling reception on the radio links used by the company to send messages to cities, ships and even aircraft in the early ‘thirties.

Most of the noises were identifiable. They were made by cars, trains, trams and the dozens of other electric motors used in the busy cities.

But Jansky’s aerials picked up one noise that he could not recognise. It was a hiss and he heard it when his aerials were pointed directly at the skies. A more careful study of the mysterious sound’s timing revealed that its peak came exactly four minutes earlier each day.

Determined to find the answer, Jansky began studying astronomy. He learned two important facts. One was that if we measure time against the motion of the stars, the length of the day is just four minutes short of 24 hours. This 23 hours 56 minutes is known as a sidereal day.

The second important point he learned was that the point of the sky from which the most noise came was in the direction of the Milky Way, the heart of our own galaxy of stars.

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This edited article about the universe originally appeared in Look and Learn issue number 676 published on 28 December 1974.

Radio astronomer

Big things were happening at the top of a mountain in California, U.S.A. Through a 100-inch telescope installed there, Edwin Hubble was exploring the universe beyond the solar system, beyond even the vast belt of billions of stars called the Galaxy, of which the solar system is a part.

As he searched the heavens, Hubble saw other galaxies, each containing billions of stars. They were so far away that they looked like patches of mist. Some were shapeless masses, others looked like spiralling Catherine wheels (like the Milky Way above) and others were lens shaped, like the picture on the left.

But the amazing thing was that each of these galaxies was opening out and moving farther and farther away from us. The most distant galaxies were travelling faster than the nearer ones.

Hubble was able to tell this because he had, as an assistant, Milton Humason, who spent hours taking photographs of the light given off by these galaxies. Last week we explained that a spectrum is the band of coloured light into which white light is changed when it is passed through a prism. Some of the galaxies were so faint, that Humason had to expose his photographic plate for 70 hours in order to make a photograph of them.

The photographs Humason took showed that dark lines crossed the spectra. The closer these were to the red end of the spectrum, the more distant was the galaxy. By their study of these photographs, Hubble and Humason were able to tell that all of the galaxies were moving farther and farther away from us and that the universe really was expanding.

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This edited article about space originally appeared in Look and Learn issue number 672 published on 30 November 1974.

A diagram showing the relative size of the planets as they orbit the sun by Clifford Meadway

Russian scientists at their space mission control centre in the U.S.S.R. watched their screens, dials and teleprinters with mounting excitement.

The aerials of their receiving equipment were picking up streams of information about a distant planet. It was coming from an un-manned space craft which had landed on Venus which, to the ancient people, was the symbol of beauty.

But as they read the data which poured from their equipment, they gasped. Their worst fears were confirmed. Far from being a pleasant place, Venus was a vast inferno. Previous probes had suggested this – and now it transpired that the surface of the planet was red hot, bubbling away at a temperature of almost 900 degrees Fahrenheit.

It was more than the super-heat resistant metal of their robot space craft could stand. After half-an-hour, it succumbed. Transmissions stopped. Was the space craft melted by the heat? Or did it slowly sink into the surface of the planet, for we do not know whether this is hard or soft. Perhaps the mystery will be solved when other space probes go to Venus, but for the moment we have to rely upon the information provided by the Russian probes, Venera 4, 5, 6, 7 and 8. And these tell us that Venus is a hostile place on which man is unlikely ever to set foot.

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This edited article about space originally appeared in Look and Learn issue number 671 published on 23 November 1974.

The ‘moon buggy’ belonging to Apollo 15 by Wilf Hardy

Built by the Boeing company, the ‘moon buggy’  was first used on the moon with the Apollo 15 moonshot. It had to be built to very exacting specifications so as to operate in the vacuum atmosphere of the moon where the temperature varies from extremes of intense heat and cold.

Designed and built in 17 months, it can carry more than twice its own weight (a normal car only carries half its own weight). This consisted of 400 lb for each astronaut and equipment, 280 lb of tools, television and communication equipment.

Its power source comes from two 36 volt batteries, each capable of powering the buggy on its own. The drive is on each wheel by an electric motor. It has a range of 57 miles and an exploration range from the moon module of six miles. This may not sound much, but should it break down, the astronauts would have found it very tiring to walk back to the moon module for anything greater than this distance.

The vehicle can be driven by both astronauts by a T-shaped hand controller located on the console between the two seats. Pushing it forward sets the vehicle in motion, pulled backwards it brakes and when turned sideways it moves the vehicle to left or right.

The moon buggy can climb slopes and go over small craters. It has seat belts to hold the astronauts, as each bump would be accentuated by the moon’s one-sixth gravity.

This vehicle was very valuable to the moon explorers because it added mobility to their assets. Because the astronauts had to expend less energy in getting about, they could stay on the moon longer.

A remotely controlled TV unit enables mission control to watch whatever is being done on the moon, the only fault being that the umbrella-like antenna can only be open for direct transmission to Earth when the vehicle is stopped and no views can be seen when the buggy is on the move.

It remains on the moon, a strange craft to intrigue future moon visitors.

This edited article about space originally appeared in Look and Learn issue number 671 published on 23 November 1974.

A cut-away image of the sun by Harry Green

Scientists aboard an American laboratory floating in space, called Skylab, had a very important job to do. They had to find out all they could about the vast, flaming mass of gas that we call the sun. For more than eight months they worked at their instruments, recording the heat at various parts of the sun, the intensity of the light and the extent of the sun’s halo.

If you look at the cut-out picture, you will see some of the things they either discovered or confirmed. This shows you how the sun produces a variety of rays and different intensities of heat. After the core, which is unimaginably hot, there are various layers of heat. Then we come to the outer edge from which spectacular flares shoot off. Forming the sun’s outer atmosphere is the corona which, although it can only be seen near the edge of the sun, extends for many millions of miles.

The sun is the centre of the solar system. Nine planets or worlds (of which Earth is one) revolve around the sun. For thousands of years, men have been looking at the sky and trying to learn about this strange solar system.

The first of the great astronomers to study it was Greek. He was Thales of Miletus who lived from 624 to 546 B.C. He is thought to have been the first person to have stated that the Earth is a globe. Aristotle, a Greek philosopher of 385 to 325 B.C. found a way of demonstrating this. He said that the Earth’s shadow, when it was seen on the Moon during an eclipse, was curved and indicated that the Earth was round.

For a long time, people thought that the sun and the planets went round the Earth. Ptolemy, Egypt’s royal astronomer in the second century A.D. put forward this theory, which was believed for more than 1,300 years. In 1543, it was challenged by a Polish priest, Copernicus, who said that the Earth and Mars went round the sun.

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