Nils Gustaf Dalen (1869-1937), Swedish engineer who won the Nobel Prize for Physics in 1912 for his invention of the automatic sun valve, or Solventil, which regulates a gaslight source by the action of sunlight, turning it off at dawn and on at dusk or at other periods of darkness. It rapidly came into worldwide use for buoys and unmanned lighthouses.
In 1906 Dalen became chief engineer of the Gas Accumulator Company, which marketed acetylene gas. He became managing director of the company in 1909 and then invented Agamassan, a substance that absorbs acetylene, making it possible to concentrate the gas with no danger of explosion. He was blinded by an explosion during an experiment in 1913, but he continued experimental work until his death.
Early Life
Dalen was born on November 30, 1896, on the Skra ddargaden farm in Stenstorp in the Vastergotland province of Sweden. He was the fourth of five children born to Anders Johannson, a farmer, and his wife Lovisa Andersdotter Dalen. All of the children adopted their mother's maiden name. Although the children were expected to take over the family farm, Lovisa also stressed the importance of education. Dalen demonstrated an early talent for invention. As a child, he became known throughout his district for devising a "bed roller" that made coffee and switched on the light. He also developed an automatic threshing machine powered by an old spinning wheel.
The accident in 1912
Early in 1912, Dalen was blinded in an acetylene explosion during a test of maximum pressure for the accumulators. Later the same year he was awarded the Nobel Prize for physics. Too ill to attend the presentation, Dalen had his brother, ophthalmologist Professor Albin Dalen of the Caroline Institute, stand in his place.
The presentation speech praised the quality of sacrificing personal safety in scientific experimentation, a compliment that compared Dalen with Nobel himself. Despite his blindness, Dalen controlled AGA until his death in 1937. He received over 100 patents during his lifetime.
Nobel Prize in Physics
