Tasimeter

The tasimeter, or Microtasimeter, or measurer of infinitesimal pressure, is a device designed by Thomas Edison to measure infrared radiation. In 1878, Samuel Langley, Henry Draper, and other American scientists needed a highly sensitive instrument that could be used to measure minute temperature changes in heat emitted from the Sun’s corona during a solar eclipse, due to occur along the Rocky Mountains on the 29 July of that year. To satisfy those needs Edison devised a microtasimeter employing a carbon button.