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:
“The history of progress is written in the blood of men and women who have dared to espouse an unpopular cause, as, for instance, the black mans right to his body, or womans right to her soul.”
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“It is the true office of history to represent the events themselves, together with the counsels, and to leave the observations and conclusions thereupon to the liberty and faculty of every mans judgement.”
—Francis Bacon (15611626)