Science Projects And Inventions

Eager to boost orders for his teas. New York tea merchant Thomas Sullivan devised a new method of distributing samples of tea to his customers. He stitched them into small silk muslin bags, making them easy to ship and less messy for the recipient to unpack. Some customers did not bother opening the cloth bag and simply poured boiling water over them. Sullivan was inundated with orders for more tea packaged in this way. Responding to suggestions that the silk mesh was too fine, Sullivan used cotton gauze instead and began to sell the bags commercially, The patent for the tea bag was registered by Sullivan in 1903. By 1920, tea bags were in wide use by the catering trade in the United States. Later, paper was used instead of cotton and a fine string and decorated tag were sometimes added, making them more convenient for drinkers making a single more...

"It is a great advantage that every honest employment is deemed honorable, lam ...a nail maker." Thomas Jefferson, U.S. president, in a letter Nails were among the first metal objects made by hand. In Roman times, any sizable fortress would have a workshop where workmen fashioned the metal items required by the army. Here, workmen called "slitters" cut up iron bars for the attention of "nailers," who gave them a head and a point. Early nails were usually square in section, and the head of each was formed simply by turning over one end to make an L-shape. Such nails were expensive to produce, and they were so valued that people sometimes burned their houses when moving in order to retrieve nails from the ashes for reuse. In 1590 water-powered slitting mills were introduced into England. After rolling the hot iron into sheets, each sheet was slit into long, narrow, more...

The sun travels across the sky at the rate of 15 degrees per hour (reappearing at a given point after one day) and the shadow that it casts moves at a similar rate. In sunny climes the shadow has been used as a clock. The most ancient clock was the vertical obelisk. This tapering column, rather like Cleopatra's Needle in London, cast a shadow that varied in its length and orientation as the day progressed. The Egyptians had a small, portable shadow clock. It consisted of a T-shaped bar that lay on the ground, except that close to the shorter crossbar was a 90-degree bend that lifted the crossbar above the long horizontal stem so that its shadow would fall on the stem. The long stem was pointed directly toward the west point on the horizon in the morning. At noon, it was pointed in the reverse direction, toward the more...

Although the first zoom lens was invented in 1901 by Clile C. Alien, its popularity in sales terms only came in the late 1980s. Prior to this the fixed-focus lens was the standard; however, this was pushed aside because of the physical effort required to photograph different- sized subjects. With a fixed-focus lens, the only way to adjust the amount captured in a photograph is to physically move backward or forward with the camera. A zoom lens works by allowing the photographer to widen or shorten the focal length, which increases or decreases the magnification of the subject. The focal length is the distance between the lens and the point in the camera at which the light rays converge. Changing this length allows you to zoom in and out when taking a photograph. There are many different designs of zoom lens. Some may be composed of up to thirty individual more...

“I soon learned that it did not require a great brain to do original research." Julius Axelrod Despite earning a degree in biology, American biochemist Julius Axelrod (1912-2004) was rejected from all the medical schools he applied to and so got a laboratory technician job in New York's public health department, looking at vitamins in food. He attended night school to get a master's degree in science in 1942, then worked under scientist Bernard Brodie (1909-1989) at Goldwater Memorial Hospital in 1946. During the 1940s the use of nonaspirin-based pain analgesics was being linked to the blood-poisoning condition methemoglobinemia. Axelrod and Brodie wanted to find out why Their detailed research found acetanilde, the main ingredient in many of these products, degraded into the blood toxin aniline. They suggested this was the most likely cause. They also discovered that one of its breakdown products also worked to kill pain in the more...

Micro-Electro-Mechanical Systems, or MEMS, are specialized silicon chips that incorporate not only miniaturized  electronic  circuits  (the "electro" component) but also a "mechanical" part, such as tiny arms, gears, or springs. These chips, therefore, may possess not only the ability to process data, but also, etched into its surface, the ability to collect data in the form of some kind of sensor. Needless to say, the sensors are tiny, going down to the scale of millionths of a meter, or micrometers. The term MEMS is itself thought to have arisen as a consequence of a 1987 gathering, called the Micro Robots and Teleoperators Workshop, conducted by the International Electrical and Electronics Engineers." Later, in 1988, a reliable method of bonding silicon components onto silicon chips was demonstrated. Controllers in some video games, for example, utilize tiny accelerometers within their control pods to measure tilt, shock, and acceleration. While this is obviously more...

"Many remains of....stone architecture exhibit forms [that imitate] construction in wood." John Capotosto, writer  Before the discovery of metallurgy, long before plastics, the materials that Stone Age man used were those that he found around him in nature: stone, mud, bone, and of course wood. Wood is an extremely important material, having numerous useful properties; it floats, it burns, and it can be shaped relatively easily into a variety of different objects. The craft of shaping and using wood—carpentry—has its roots in prehistoric times. Early woodwork consisted of the use of wood for basic tools, but there is also archeological evidence that Neanderthals were shaping wood into new forms as long ago as the middle Paleolithic (Old Stone Age, 300,000 to 30,000 years ago), using tools made from flint and stone. In this way many useful things were created from wood, including fire-hardened spears and logs hollowed out to create more...

On May 6, 1840, in the greatest single reform of the English postal system since its inception in 1510, the world's first prepaid adhesive postage stamp, the Penny Black, was issued. The stamp ushered in the era of prepaid post and was instrumental in lowering postal rates. By 1856 the number of letters posted annually in Britain had grown to almost 400 million, compared to a mere 76 million in 1839. The Penny Black, graced by the profile of England's young Queen Victoria, was designed by postal service employee Rowland Hill (1795-1879). In 1837 Hill authored and circulated a pamphlet titled Post Office Reform: Its Importance & Practicality, in which he tackled the reasons for the complexity and often prohibitive costs involved in delivering Britain's mail. Prior to 1840, prepaid postage was purely voluntary. However, where the letter was not already paid for, the cost of delivering it had to more...

"Abe Lincoln may have freed all men, but Sam Colt made them equal". Popular post-American Civil War slogan Samuel Colt (1814-1862) produced the first revolver capable of firing five or six times without reloading. It was equipped with a cylinder containing chambers into which bullets were loaded. The cylinder would revolve with each cock of the hammer, enabling each chamber to. lock into position behind the barrel and discharge the bullet with a pull of the trigger. In anticipation of demand for the revolver, Colt opened a manufacturing plant, but poor sales forced its closure. Co-It's fortunes changed after favorable reports from U.S. troops fighting in Florida and Texas instigated a government order for 1,000 pistols. With the assistance of Eli Whitney Jr., Colt opened the world's biggest armory in Hartford, Connecticut, developing a production line of handguns and interchangeable parts. By 1856 the company was gaining a reputation around more...

A water bed consists of a heated, water-filled mattress inside either a "hard-sided" rectangular wooden frame or a "soft-sided" robust foam frame. Both types rely on a strong metal platform to bring the mattress to a convenient height. Early models had only one water chamber within the mattress, making it very bouncy, but later designs incorporated fiber blocks and several interconnected water chambers to reduce the wave action. Some modern water beds comprise a mixture of water and air chambers. Thermostatically controlled electrical heating pads usually maintain the water at body temperature, at around 86°F (30°C). In 1883 Dr. William Hooper of Portsmouth, England, obtained a British patent for a water bed designed for patients at risk of developing bedsores. However, his model lacked the technologies to ensure that the beds were watertight, and he was unable to control the water temperature, so his invention was not a commercial success. more...