History
After the discovery of radioactivity by Henri Becquerel in 1896, it was generally believed that atmospheric electricity, ionization of the air, was caused only by radiation from radioactive elements in the ground or the radioactive gases or isotopes of radon they produce. Measurements of ionization rates at increasing heights above the ground during the decade from 1900 to 1910 showed a decrease that could be explained as due to absorption of the ionizing radiation by the intervening air.
Read more about this topic: Cosmic Ray
Famous quotes containing the word history:
“A man acquainted with history may, in some respect, be said to have lived from the beginning of the world, and to have been making continual additions to his stock of knowledge in every century.”
—David Hume (1711–1776)
“Gossip is charming! History is merely gossip. But scandal is gossip made tedious by morality.”
—Oscar Wilde (1854–1900)
“The history of the past is but one long struggle upward to equality.”
—Elizabeth Cady Stanton (1815–1902)