"In 1941 virtually no metallurgist in the U.S. had seen a piece of ductile titanium..." First International Titanium Conference, 1968 Reverend William Gregor discovered titanium as a metal oxide in 1791. Isolating pure titanium proved a herculean task, first done 100 years after its oxide was found. Matthew Hunter of Rensselaer Polytechnic University in the United States accomplished the tasMore.
A blink comparator enables astronomers to look at two different photographic plates taken of the same region of the sky on different nights, using the same telescope and plate exposure. If something "blinks" as the view rapidly switches from one illuminated plate to the other, the object has either changed brightness or moved. This apparatus and technique has been used to detect asteroids, cometsMore.
Most kinds of mechanical movement in appliances are driven by electric motors—fans, fridges, and even computers are all powered in this way. In 1873 Frenchman Theophile-Zenobe Gramme (1826-1901) was the first to show that electricity could be used to move things efficiently. Semiliterate, and with only a grasp of simple arithmetic, he was not a typical inventor. However, his manual skill andMore.
The innocuous spray can has been the subject of some controversial press coverage over the years. Its use as a cheap means of getting "high," termed solvent abuse, involves inhaling the fumes of certain aerosols to achieve an effect a little like being drunk. The aerosol can is also popularly used to spray-paint graffiti and, during the 1970s, the increasing awareness that chlorofluorocarbons wereMore.
The steam shovel, invented in 1839 by William Otis, was used to dig the Suez Canal in 1869 and the Panama Canal in 1910. But eighty years after the invention of a digging machine, trenches were still being filled using mule power. In 1923, American farmer James Cummings (1895- 1981) saw mules being used to backfill oil pipeline trenches and realized that a machine could do the job more efficientlyMore.