Science Projects And Inventions

As twenty-first-century life becomes increasingly hectic, technologists continue to search for ways to reduce our burdens. "Useful" time-saving devices have included bagless vacuum cleaners, saucepans that indicate when they are hot, and cars that sound a warning when their driver is going the wrong way. Self-cleaning windows might seem to be yet another nifty, but fairly pointless, addition to this ever- growing canon of inane novelty. The innovative technology behind them is clever and effective, but how worried are people about the cleanliness of their windows? It turns out that they are quite concerned about it. PPG Industries, which pioneered the first self- cleaning windows in 2001, carried out consumer research through a survey in Better Homes & Gardens magazine in 2000, and self-cleaning windows came out at the top in a list of fantasy products. The windows (named Sun Clean by PPG) are self- cleaning because an extremely thin more...

"The condom is an armor against enjoyment and a spider web against danger." Madame de Sevigne, writer The Italian anatomist Gabriele Falloppio (1523-1562) posthumously published the first description of the condom in De Morbo Gallico (1564), a treatise on syphilis. To help counter the spread of the sexually transmitted disease, Falloppio invented a linen sheath that, when dipped in a solution of salt, formed a protective barrier during intercourse. To attract the ladies, the condoms were secured by pink ribbons. Falloppio claimed that none of the 1,100 men who used the device became infected with syphilis. This is not to say Falloppio's condom was the first. Cave paintings from Combarelles in France and drawings from ancient Egypt have been found depicting men wearing condoms. Over the years condoms have been made from oiled paper, thin leather, fish bladders, and even tortoiseshell. By 1844 Charles Goodyear (of tire fame) had patented more...

It is a medical practitioner's dream—a drug that will affect only the metabolism of a virus or cancer, with no side effects for the patient—the so-called "magic bullet." U.S. scientists George Hitchings (1905-1998) and Gertrude Elion (1918-1999) produced not one but a whole line of these type of medicines. Hitchings hired Elion to work in his lab in 1944, and together they conducted experiments to study the differences between how DNA is synthesized in normal human cells, cancerous cells, bacteria, and viruses. They created new compounds similar to nucleic acids—the building blocks of DNA—that would interfere with the virus (or cancer) cell's ability to reproduce, but would not affect normal healthy human cells. Their work went on to revolutionize the way drugs were developed because they came up with the idea of "rational" drug design. Instead of the usual, time-consuming, trial and error method of hoping to find a chemical more...

William Murdock (1754-1839) was a consummate and prolific inventor, but the invention that he is most remembered for today was the development of gas lighting, which took over from the oil and tallow system. His experiments began around 1792 when he realized that gases released from burning coal could be lit and used as a steady source of light. He is said to have burned coal in his mother's old kettle, lighting the gas that came out of the spout. By 1794, however, the kettle had been replaced by a specially built retort in which the coal was burned; gas from the burning coal was tunneled through a long attached tube, to be ignited at the tube's end. Murdock first used his system of gas lighting in his own home in Redruth, Cornwall, and continued to develop methods for producing, storing, and igniting the gas more efficiently and practically In more...

"Sucking out dust is impossible. It has been tried over and over without success..." John S. Thurman, inventor In 1901 mechanical engineer Hubert Cecil Booth (1871-1955) watched a railway carriage being cleaned at St. Pancras Station in London by a series of high- pressure hoses using compressed air to blow away debris. Dining with friends afterward, he impulsively covered his mouth with a moistened handkerchief, placed his mouth against the cover of his cloth chair and inhaled, trapping dust against the outer lining of the handkerchief. Convincing himself that a device using reverse pressure and equipped with a filter would effectively capture and store dust, he set about creating a cleaning machine using suction rather than simply blowing particles into the air. Together with his friend F. R. Simms, who designed a water-cooled, six-horsepower piston engine driven by an electric motor, to which Booth attached a simple vacuum pump, he more...

The very first stapler is thought to have belonged to King Louis XV of France. The elaborate, handmade staples were imprinted with the royal insignia and were used to fasten together court documents. In 1868 Charles Gould received a British patent for a wire stitcher that could be used to bind magazines. His invention used uncut wire that was then cut to length, the pointed ends forced through the paper, and the ends folded down. The device was a direct predecessor of the modern stapler. In the United States, in 1868, Albert Kletzker patented a type of paper clip that used a single large staple to fasten together papers but did not crimp the ends, which had to be done by hand. The first machine that both inserted the staple and crimped it in one motion was patented by Henry R. Heitin 1877. The first commercially successful stapler was produced more...

"...a lanthorn, with pictures on glass, to make strange things appear on a wall, very pretty." Samuel Pepys, diarist The "magic" lantern was used to project still images onto a wall or sheet and was an early version of the slide projector. The idea has been understood for many centuries. Light, shining through a translucent picture, will project the image onto a light-colored flat surface. The earliest reference to the use of a lantern to project images is in Liber Instrumentorum by Giovanni de Fontana, written around 1420. Optics developed rapidly in Europe during the seventeenth century. As early as 1659, Dutch scientist Christiaan Huygens (1629-1695) had made a lantern with a lens to focus the light and produce a sharp image. Danish mathematician Thomas Walgensten (1627-1681) traveled throughout Europe in the 1660s, selling the lanterna magica. Numerous designs survive from this period and, in 1663, optician John Reeves of more...

"And they said to one another,  'Come, let us make bricks, and burn them thoroughly.'" Genesis 11:3 In ancient times, brick houses were made first, by compacting together wet mud and clay into slabs and leaving them to dry in the sun. Once solid, the bricks were piled up to fashion a basic building. However, the major problem with sun-dried bricks is that rainy weather can revert them to wet mud. It took brick makers a long time to arrive at a solution—buildings were constructed from dried mud blocks for more than 5,000 years before the fired brick appeared. Using a combination of clay, sand, and water, brick makers in the Middle East formed a pliable mass of matter called a clot. The clot was shaped in a wooden mold to create what is known as a "green" (that is, unfired) brick. This was placed in a kiln and baked more...

"I hit upon the idea of a chocolate bar dispenser, but replacing chocolate with cash." John Shepherd-Barron There was a time not so long ago when there was no such thing as a cash machine. If you wanted to withdraw some money, you had to go into a building and speak to a teller. Now, of course, it is possible to get cash from one of .over 1.6 million automated telling machines (ATM) worldwide, in stores, cinemas, and even the southern rim of the Grand Canyon. Exactly who we have to thank for this stroke of technological banking genius is a matter of some controversy. Luther George Simjian, a prolific inventor of his time, devised the very first "cash-point" in 1939. Installed by the City Bank of New York this cash machine saw little use except with "... prostitutes and gamblers who didn't want to deal with tellers face to more...

"Give me a lever long enough and a fulcrum on which to place if and I shall move the world" Archimedes, mathematician and physician The lever was first described in 260 B.C.E. by Archimedes (c. 287-212 B.C.E.), but probably came into play in prehistoric times. A lever can be used to raise a weight or overcome resistance. It consists of a bar, pivoted at a fixed point known as the fulcrum. Extra power can be gained for the same effort if the position of the fulcrum is changed. Levers may be divided into classes. First-class levers have the fulcrum in between the applied force and load, which are at opposite ends, such as with the seesaw. Second-class levers have the fulcrum at one end, and the applied force at the other, such as with a bottle opener. Finally, third-class levers have the effort in between the fulcrum and the load; more...