For centuries smallpox was one of the world’s most-dreaded plagues, killing as many as 30 percent of its victims, most of them children....
1. D For centuries smallpox was one of the world’s most-dreaded plagues, killing as many as 30 percent of its victims, most of them children. But smallpox was also one of the first diseases to be controlled by a vaccine, following the great experiments of English physician Edward Jenner in 1796.
2. B The image-forming process that relies on a photoconductive substance whose electrical resistance decreases when light falls on it, Xerography is the basis of the most widely used document-copying machines. The process was invented in the 1930s by U.S. physicist Chester F. Carlson and developed in the 1940s and ‘50s by Xerox Corp. (then called Haloid).
3. D The Egyptians developed a substance more closely resembling modern concrete by using lime and gypsum as binders. Lime (calcium oxide), derived from limestone, chalk, or oyster shells, continued to be the primary pozzolanic, or cement-forming, agent until the early 1800s.
4. A British computer scientist Tim Berners-Lee is generally credited as the inventor of the World Wide Web and was awarded a knighthood by Queen Elizabeth II of the United Kingdom in 2004. In 1994, in the United States, he established the World Wide Web (W3) Consortium at the Massachusetts Institute of Technology’s Laboratory for Computer Science.
5. C American inventor Douglas Engelbart’s work beginning in the 1950s led to his patent for the computer mouse. A mouse is a hand-controlled electromechanical device for interacting with a digital computer that has a graphical user interface. It can be moved around on a flat surface to control the movement of a cursor on the computer display screen.
6. D British engineer Sir Christopher Sydney Cockerell, who invented the hovercraft, began testing his ideas for a vehicle that moved atop a cushion of air in 1955. His first hovercraft prototype, the SR.N1, was launched in the spring of 1959. The SR.N1, a four-ton vehicle, could carry only its crew of three, and crossed the English Channel for the first time on July 25, 1959.
7. B The first implantable cardiac pacemaker was developed by Wilson Greatbatch, an American electrical engineer. His original pacemaker was first implanted in a human in 1960, and by 1972 Greatbatch had succeeded in extending the life of the battery to 10 or more years.
8. D German craftsman and inventor Johannes Gutenberg originated a method of printing from movable type. Elements of his invention are thought to have included a metal alloy that could melt readily and cool quickly to form long-lasting reusable type, oil-based ink that could be made sufficiently thick to adhere well to metal type and transfer well to vellum or paper, and a new press, likely adapted from those used in producing wine, oil, or paper, for applying firm even pressure to printing surfaces.
9. C René Laënnec was a French physician who invented the stethoscope and perfected the art of auditory examination of the chest cavity. In 1816 Laënnec was appointed as a physician at the Necker Hospital in Paris, where he developed the stethoscope. Laënnec’s original stethoscope design consisted of a hollow tube of wood that was 3.5 cm (1.4 inches) in diameter and 25 cm (10 inches) long and was monoaural, transmitting sound to one ear. It could be easily disassembled and reassembled, and it used a special plug to facilitate the transmission of sounds from the patient’s heart and lungs.
10. B The Russian-American pioneer in aircraft design, Igor Sikorsky, is best known for his successful development of the helicopter. In May 1909, he began construction of a helicopter, and in early 1939, with a well-trained engineering group at his disposal, he started the construction of the VS-300 helicopter. The VS-300 was small (weighing 1,092 pounds) and was powered by a 65-horsepower Lycoming engine. On September 14, 1939, the VS-300 lifted off the ground on its first flight.
