SOME PRACTICAL INVENTIONS QUIZ

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Across
  1. 4. Which is a method of graphic tracing of the electric current generated by heart muscle during a heartbeat, first developed by Dutch physiologist Willem Einthoven in 1903?
  2. 6. Which diagnostic imaging method uses a low-dose beam of X-rays that crosses the body in a single plane at many different angles?
  3. 7. In 1914 the world’s first two electric traffic lights were installed in which American city?
Down
  1. 1. Which electrostatic dry-copying process, invented by Chester F. Carlson, was used to quickly create reproductions of documents?
  2. 2. In 1908 Swiss chemist Jacques E. Brandenberger designed a machine for continuous production of which strong transparent film?
  3. 3. In the 1940s Swiss engineer George de Mestral saw tiny hooks on the burrs clinging to his hunting jacket and invented the hook-and-loop fastener system known as what?
  4. 5. Which was the first practical color photography process, introduced in France in 1907 by Auguste and Louis Lumière?