Tire placard pressure is often much lower than listed on the tire sidewall. Air pressure given by the vehicle maker was based on the tires supplied with the vehicle. They design many newer replacement tires to give a good ride, with much more pressure.
Fresnel lens. A Fresnel lens is a type of lens invented by Augustin-Jean Fresnel. Originally developed for lighthouses, the design enables the construction of lenses of large size and short focal length without the weight and volume of material which would be required in a lens of conventional design. Detailed information.
Gyroscope Compass: History of Sperry Marine. Biographies on inventor Elmer Sperry and the history of gyroscope compasses. Elmer Sperry-Sperry Gyroscope. Elmer Sperry invented the gyroscopic compass or Sperry Gyroscope.Elmer Ambrose Sperry. Elmer Sperry invented gyroscope guided automatic pilots for ships, airplanes, and spacecraft. year earlier (1851) Leon Foucault invented the Foucault pendulum which he used to measure the Earth's rotation. Among his other achievements: in 1850, Foucault proved that light traveled more slowly in water than in air; and in 1858 Foucault made an improvement to the mirrors used in reflecting telescopes.