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 Rays
Famous quotes containing the word history:
“It is remarkable how closely the history of the apple tree is connected with that of man.”
—Henry David Thoreau (1817–1862)
“These anyway might think it was important
That human history should not be shortened.”
—Robert Frost (1874–1963)
“The only thing worse than a liar is a liar that’s also a hypocrite!
There are only two great currents in the history of mankind: the baseness which makes conservatives and the envy which makes revolutionaries.”
—Edmond De Goncourt (1822–1896)