Archives June 2013

"This device is... the only thing of its kind. The design is beautiful the astronomy is exactly right." Professor Michael Edmunds, Cardiff University One of the most remarkable inventions of the ancient world came to light in 1900 when a Greek sponge diver discovered the wreck of an ancient Greek or Roman cargo ship that had sunk off the Greek island of Antikythera around 80 B.C.E. Among the objects recovered from the wreck was a geared mechanism that, from the shape of its inscribed Greek letters, dated to between 150 and 100 B.C.E. The mechanism has more than thirty gearwheels and three main dials. When reassembled, it formed a scientific instrument that could be used to calculate the astronomical positions of the sun, moon, and the five planets then known. When a date was entered via a crank, now lost, the mechanism calculated the position of the sun, moon, or more...

"Iron weapons revolutionized" — warfare and iron implements .. did the same for farming" Alan W. Cramb, Professor of Engineering The use of metals to make tools, weapons, or Jewelry has been one of humanity's pivotal achievements. Manipulated metals are everywhere, from kitchen utensils to high-tech weapons and tools. Even items that contain no metal are likely to owe some debt to a metal tool that was used in their construction. As near as archeologists can tell, the love affair between humans and metals probably began around 8700 B.C.E., evidenced by a copper pendant found in northern Iraq. Smelting, the extraction of metal from a metal-containing rock, began around 5000 B.C.E. when copper ores were melted to get at the metal. By 4000 B.C.E. people were using gold and adding arsenic to copper to create arsenical bronze, probably the first man-made alloy, or metal mixture. Although harder than copper, arsenical more...

Fire alarms were originally raised by ringing church bells. Due to the nature of sound, bells had the huge disadvantage of being affected by environmental conditions, making finding the fire extremely difficult. In 1845 American William Channing proposed using Samuel Morse's telegraph system to raise the alarm and coordinate a, response. His system comprised signal boxes that would send automated messages of their location (and hence the fire) to a central office. The fire-alarm signal-box system is still used in the United States and is akin to the manual "break-glass" fire call point more commonly used in Europe. In the central office an operator would forward the message to all other signal boxes within the circuit. At the same time electrical impulses would be sent to automatic bell strikers to sound the alarm and alert the firefighters, who at that time were mostly volunteers. By going to their nearest signal more...

"Blowing allowed for previously unparalleled versatility and speed of manufacture." Rosemarie Trentinella, Metropolitian Museum of Art It was the Syrians who first learned to blow molten glass through a hollow metal tube and shape it into intricate forms. Although the technique for producing glass had existed for about two and a half millennia, it was only in approximately "100 B.C.E. that the hazardous art of glassblowing—using glass melting at a few thousand degrees Fahrenheit—was mastered. Glassblowing is the process for forming glass into a desirable shape, and this ability to form iconic, practical, and elegant shapes out of glass has been of incalculable value and practical benefit to society. Glassblowing machines have now largely replaced the Syrian specialists, but the science behind the technique remains the same. Molten glass is first introduced to the end of a hollow tube. A bubble of air is then blown through the tube, and more...

There is a famous saying that the role of pen is mightier than that of the sword. But unfortunately there are people who believe that the use force is necessary.   The pen expresses a personal or public opinion. It stands for the press, literature, newspapers, books, and other  writings. The purpose of all writing is to connect one's mind with another, to persuade the reader to take up the view which the writer holds on a particular subject. The reader has the right to hold his own view; he may not be convinced of the writer's judgement and opinions presented to him. We may, therefore, say that the pen stands for the peaceful means by which a person is persuaded to accept the views which the writer holds. No force is used to persuade the reader, but a good and forceful writer forms opinion. But the sword, on the more...

"He [Papin] doth not think... that any thing better can be made for such things, as must be stew'd...." Denis Papin, Philosophical Transactions (1683-1775) There is a story that when French scientist and inventor Denis Papin (1647-1712) first demonstrated his wonderfully named "digester" to London's Royal Society in 1679, the device exploded. So another invention swiftly came into being: Papin's safety valve, which went on to have other applications. By 1682, a refined version of the steam digester proved excellent at cooking food and making nutritious bones soft and tasty. After a demonstration dinner at the Royal Society in that year, one guest, leading horticulturalist John Evelyn, noted in his diary that food served up from the digester was among "the most delicious that I have ever seen or tasted." Papin was an interesting character of diverse scientific interests. Trained in medicine as a young man, he had long been more...

The electric type-printing telegraph of Royal Earl House (1814-1895) looked like the offspring of a record player and a piano. Several intricate devices sat on the telegraph's wooden base above a keyboard whose keys were labeled with the letter to which they corresponded. Despite its looks, the machine was not musical. It did, however, rely on the steady beat of its underlying clockwork-generated electricity to produce a message printed on a strip of paper. House eventually shared his idea with Jacob Brett, a British electrical engineer, who built a working model. When a key on the machine's keyboard was pressed, an electric circuit would be temporarily broken at one of twenty-eight corresponding pins on an underlying rotating cylinder. The breaking of the circuit would stop the cylinder's motion, consequently stopping a synchronized electromagnet controlling the type-wheel. With the type-wheel halted on the proper letter, the connected apparatus then pressed a more...

While some fear the invasion of privacy contingent on DNA databases produced from DNA fingerprinting, it is undeniable that the technique has had a positive impact in areas such as forensics, paternity testing, and animal classification. After studying at Oxford University, biochemist Alee Jeffreys (b. 1950) became a professor in 1977 at the University of Leicester, where he worked on DNA variation and genetic evolution in families. He studied inheritance patterns of disease, specifically in what are called "mini-satellites," or areas of great genetic variation that occur in the human DNA sequence outside of core genes. In 1984, while studying mini-satellites in the DNA of seals, Jeffreys tested a probe made of DNA on samples from various different people using X-ray film. When he developed the film, he saw what he described as a "complicated mess." Upon closer examination, however, he realized that certain patterns occurred that varied greatly from more...

From the early 1990s, as Internet usage first began to proliferate, users quickly saw the potential for sharing music. But a combination of basic connection speeds and large file sizes made uploading and downloading a painfully slow process. As early as 1987, Germany's prestigious Fraunhofer Institute had been engaged in researching high-quality, low bit-rate audio coding: in short, how an audio file can be compressed in size without affecting its sound quality. The format they came up with in 1989 was called MPEG (Moving Picture Experts Group) Audio Layer III, or MP3. MP3 compression is a simple concept to understand—even if the process itself is highly complex. A compact disc (CD) stores its information digitally, in binary digits (bits); every second of stereo music contained on a CD consists of 1,411,200 bits. MP3 compression reduces the number of bits in a recording by taking out "unnecessary" information. It does this more...

"Defibrillators should be as common as fire extinguishers." Michael Tighe, saved by a portable defibrillator A defibrillator is a device that delivers an electric shock to the heart through the chest wall, with the aim of restoring a regular rhythm. It is used to treat ventriculat fibrillation, a condition where the heart muscle is no longer contracting in a coordinated fashion, thus preventing blood from being pumped around the body. If untreated, death frequently results. American cardiac surgeon Claude Beck (1894-1971) performed the first successful defibrillation procedure in 1947 at Case Western Reserve University in Cleveland, Ohio. Beck had been operating on a fourteen-year-old boy with a congenital heart problem, and had just closed the boy's chest when he suffered a cardiac arrest. Beck immediately reopened the chest and, after unsuccessfully massaging the heart by hand, tried out the defibrillator device that he was in the process of developing. Beck's more...