Notes - Four Revolutions in the Earth Sciences - page 270

Transactions of Foreign Academies of Science and Learned Societies, and from Foreign Journ-
als (R. and J. E. Taylor, 1846), 85.
15 . Ibid., 53.
16 . A. S. Eve et al., Life and Work of John Tyndall (Macmillan & Co., 1945), 392.
17 . The Serbian geophysicist and astronomer Milutin Milankovitch (1879-1958), while in-
terned during the First World War, proposed the theory that scientists eventually accepted. After
a laborious set of calculations, Milankovitch concluded that changes in three astronomical vari-
ables had combined to cause the Ice Ages: the distance of the Earth from the Sun, the tilt of the
Earth's axis, and the “wobble” of the axis, known as the precession of the equinoxes. On a regu-
lar cycle, these engender the cooling that initiates an ice age. The instruments and the data to
corroborate Milankovitch's theory finally became available in the 1960s and 1970s.
18 . J. Tyndall, “On the Transmission of Heat of Different Qualities Through Gases of Differ-
ent Kinds,” Proceedings Royal Institution of Great Britain 3 (1859): 158.
19 . J. Tyndall, “The Bakerian Lecture: On the Absorption and Radiation of Heat by Gases and
Vapours, and on the Physical Connexion of Radiation, Absorption, and Conduction,” Philosoph-
ical Transactions of the Royal Society of London 151 (1861): 28-29.
20 . J. Tyndall, “XXVII. On Radiation Through the Earth's Atmosphere,” The London, Edin-
burgh, and Dublin Philosophical Magazine and Journal of Science 25, no. 167 (1863):
204-205.
21 . Ibid., 205.
Tedious Calculations of Extraordinary Interest
1 . The versatile Langley later went on to pursue an interest in manned flight, first having to
teach himself the principles of aerodynamics. In 1896 he launched the first aircraft powered by
steam, but it failed to fly. Seven years later a catapult flung Langley's first manned aircraft aloft,
with a brave young man named Charles Manley “at the controls.” The airship plummeted into
the Potomac River, but the intrepid Manley survived to try again. That effort also failed. Nine
days later Wilbur and Orville Wright made history at Kitty Hawk.
2 . Letter from Langley to J. Tyndall, “Action of Free Molecules on Radiant Heat, and Its Con-
version Thereby Into Sound,” Philosophical Transactions of the Royal Society of London 173
(1882): 353.
3 . V. Ramanathan and A. M. Vogelmann, “Greenhouse Effect, Atmospheric Solar Absorption,
and the Earth's Radiation Budget: From the Arrhenius-Langley Era to the 1990s,” Ambio
(1997).
4 . http://www.nobelprize.org/nobel_prizes/chemistry/laureates/1903/ .
5 . E. T. Crawford, Arrhenius: From Ionic Theory to the Greenhouse Effect (Canton, Mass.:
Science History Publications, 1996), 148.
6 . Ibid., 149.
7 . S. Arrhenius, “On the Influence of Carbonic Acid in the Air Upon the Temperature of the
Ground,” The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science
41, no. 251 (1896): 267.
8 . Ibid.
9 . Crawford, Arrhenius , 150.
10 . J. Uppenbrink, “Arrhenius and Global Warming,” Science 272, no. 5265 (1996).