Leonardo da Vinci (1452-1519) was an Italian inventor, artist, architect, and scientist. Da Vinci had an interest in engineering and made detailed sketches of the airplane, the helicopter (and other flying machines), the parachute, the submarine, the armored car, the ballista (a giant crossbow), rapid-fire guns, the centrifugal pump (designed to drain wet areas, like marshes), ball bearings, the worm gear (a set of gears in which many teeth make contact at once, reducing the strain on the teeth, allowing more pressure to be put on the mechanism), and many other incredible ideas that were centuries ahead of da Vinci’s time.
X-rays were discovered in 1895 by Wilhelm Konrad von Roentgen (1845-1923). Roentgen was a German physicist who described this new form of radiation that allowed him to photograph objects that were hidden behind opaque shields. He even photographed part of his own skeleton. X-rays were soon used as an important diagnostic tool in medicine. Roentgen called these waves “X-radiation” because so little was known about them.
The paper clip was invented in 1899 or 1890 by a Norwegian patent clerk called Johann Vaaler. His original paper clip was a thin spring-steel wire with triangular or square ends and two “tongues.” Vaaler patented his invention in Germany and later in the USA (1901).
The modern-shaped paper clip was patented in April 27, 1899 by William Middlebrook of Waterbury, Connecticut, USA.
John S. Thurman invented the gasoline powered vacuum cleaner (which he called the “pneumatic carpet renovator”) in 1899. His vacuum was patented on Oct. 3, 1899 (patent #634,042). It may have been the first motorized vacuum cleaner. Thurman had a run a horse drawn, door-to-door carpet vacuuming service in St. Louis, Missouri, USA, charging $4 per visit (which was a large amount of money at the time).
Coenraad Johannes Van Houten (1801-1887) was a Dutch chemist and chocolate manufacturer who in 1828 invented the process that is used to turn roasted cacao beans (the source of chocolate) into cocoa powder (this process is now called Dutching, Dutch processing or alkalinisation). His method was an inexpensive way of removing much of the cocoa butter from the nib (center) of the beans, using a hydraulic press, and adding alkaline salts (potassium carbonate or sodium carbonate) so that the cocoa powder would mix readily with water or milk (the alkali neutralized the acidic chocolate). The resulting cocoa powder can be used to make chocolate milk and other delicacies.
George de Mestral was a Swiss engineer who invented Velcro in 1948. While hiking, he had noticed that burrs (burdock seeds) stuck to his clothing extraordinarily well. The burrs had hook-like protrusions that attached themselves firmly to clothing. Mestral used this same model to develop Velcro, which consists of one strip of nylon with loops, and another with hooks. Mestral patented Velcro in 1957. It was originally used mostly for fastening clothes, but is now used to fasten many other things.
John Venn (1834 - 1923) was an English mathematician who invented the Venn diagram. His diagram clearly shows the similarities and differences for two different entities; it is a visual way to represent sets, and their unions and intersections.
Lucien Vidie was a French scientist who invented the aneroid barometer in 1843. A barometer is a device that measures air (barometric) pressure. It measures the weight of the column of air that extends from the instrument to the top of the atmosphere. There are two types of barometers commonly used today, mercury and aneroid (meaning “fluidless”). The aneroid barometer uses a spring balance instead of a liquid; it is easy to transport and easy to construct.
Count Alessandro Giuseppe Antonio Anastasio Volta (Feb. 18, 1745- March 5, 1827) was an Italian physicist (at the University of Pavia) who invented the chemical battery (also called the voltaic pile) in 1800. This invention provided the first generator of continuous electrical current. Volta also discovered (and isolated) methane gas, CH4 (in 1778). He had earlier invented the electrophorus, a device that generated static electricity charges (in 1775). The volt, the unit of electrical potential, was named for Volta in 1881.