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Authors: Gabrielle Walker

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So many books have been written about the
Titanic
disaster that I will highlight only a few. Try John Booth and Sean Coughlan's
Titanic: Signals of Disaster
(White Star Publications, 1993), and Walter Lord's
A Night To Remember
(London: Longmans Green & Co., 1958). Jack Thayer's memoir of the night, "The Sinking of the SS Titanic," is vivid and shocking, but unfortunately also hard to find. It was originally published in 1940, and reprinted by 7C's press in 1974, but both editions are now out of print.

For Appleton, by far the best source is Ronald W. Clark's
Sir Edward Appleton, G.B.E., K.C.B., F.R.S.
(Oxford: Pergamon, 1971). There are also useful entries in the
Dictionary of Scientific Biography
and in the memoir written by one of his students: J. A. Ratcliffe,
Biographical Memoirs of Fellows of the Royal Society,
vol. 12 (1966),
[>]
.

CHAPTER
7

For the story of James Van Allen's discovery of the Van Allen belts, an excellent place to start is Constance McLaughlin Green and Milton Lomask's
Vanguard: A History,
NASA SP-4202 (Washington, D.C.: Smithsonian Institution Press, 1971). The book is now out of print, but it's available online at
http://www.hq.nasa.gov/office/pao/History/SP
-4202/
cover.htm.

Van Allen's own account is in "What Is a Space Scientist? An Autobiographical Example," in
Annual Review of Earth and Planetary Sciences,
June 1989. See also his article "Radiation belts around the Earth" in
Scientific American,
vol. 200, no. 3 (March 1959),
[>]
, and his
Origins of Magnetospheric Physics
(Washington, D.C.: Smithsonian Institution Press, 1983). Most of the information on Van Allen in this chapter came from these four sources.

More technical is the weighty "Magnetospheric Currents" in
Geophysical Monograph 28,
edited by Thomas A. Potemra (Washington, D.C.: AGU, 1983).

A good collection of articles can be found in "Discovery of the Magnetosphere," edited by C. Stewart Gillmor and John R. Spreiter, in
History of Geophysics,
vol. 7, AGU, Washington, D.C., 1997. These are partly technical, partly biographical, and include an
entry by Van Allen himself. "The James Van Allen Papers" by Christine Halas is at
http://www.lib.uiowa.edu/spec-coll/Bai/halas.htm
. This discusses the University of Iowa Van Allen collection, and also contains some entertaining anecdotes about Van Allen himself.

For more information about the science of the magnetosphere, as well as further details on the history of its discovery, see David P. Stern's excellent article in
Reviews of Geophysics,
vol. 40, no. 3 (September 2002), pp. 1-1 to 1-30. This is also available on the Web at
http://www.phy
6
.org/Education/bh
2_2
.html
. Also accessible and entertaining are "Watch out, here comes the sun" by Hazel Muir,
New Scientist,
February 3, 1996, p. 22, for space weather, and "Into the sphere of fire" by Stephen Battersby,
New Scientist,
August 2, 2003, p. 30, for a marvelous description of the magnetosphere's bizarre habits.

Kristian Birkeland's own description of his aurora field trips is in
The Norwegian Aurora Polaris Expedition 1902–1903,
vol. 1, sections 1 and 2 (Oslo: H. Aschehoug & Co., 1913). The introduction gives rich details of the troubles faced by the teams. (The book is labeled "Volume 1" because there should have been a second volume dealing explicitly with auroras. However, it was never published, and some have speculated that the manuscript went down with a ship carrying Birkeland's affairs after his death.)

For more on Birkeland's life, see A. Egeland and E. Leer, "Professor Kr Birkeland: His life and work," in
IEEE Transactions on Plasma Science,
vol. PS-14, no. 6 (December 1986). This contains many biographical details, as well as fascinating information on Birkeland's solar system studies, such as the functioning of the sun and the rings of Saturn. Other useful papers by Alv Egeland include his excellent "Kristian Birkeland: The Man and the Scientist" in "Magnetospheric Currents,"
AGU Geophysical Monograph 28
(Washington, D.C., 1984), pp 1–16. This monograph also contains several other useful papers, notably A. J. Dessler's "The evolution of arguments regarding the existence of field-aligned currents,"
[>]
. For an entertaining account of the electromagnetic gun fiasco, see Egeland's paper "Birkeland's Electromagnetic Gun: A Historical Review,"
IEEE Transactions on Plasma Science,
vol. 17, no. 2 (April 1989),
[>]
. Egeland also cowrote a diligently researched and documented biography of Birkeland with William J. Burke,
Kristian Birkeland: The First Space Scientist
(Dordrecht, Netherlands: Springer, 2005).

Lucy Jago has also written a biography of Birkeland:
The Northern Lights: How One Man Sacrificed Love, Happiness and Sanity to Unlock the Secrets of Space
(London: Hamish Hamilton, 2001). This book is fascinating, well written, and clearly extensively researched. But beware: Exasperatingly, the author has included no direct references or footnotes and says herself that she has "telescoped" some events to help the story along and also made "reasonable" assumptions in some unspecified cases. Unfortunately, this makes it hard to trust any of the details unless they're corroborated by another source.

For personal reminiscences of Birkeland's unique style, see the memoir written by his former lab assistant, Olaf Devik: "Kristian Birkeland as I knew him," in "Birkeland Symposium on Aurora and Magnetic Storms," edited by A. Egeland and J. Holtet (Paris: CNRS, 1968).

And finally, for more on the northern lights themselves, see Asgeir Brekke and Alv Egeland,
The Northern Lights
, translated by James Anderson (Oslo: Grøndahl Dreyer, 1994). This is a marvelous tapestry weaving together myths and legends, literature, history, and science to give a full portrait of human responses to the northern lights. There are also some fabulous illustrations.

ENDNOTES

CHAPTER
1

[>]
 
a combination of divine revelation, and abstract reasoning
The intellectuals thus occupied claimed a Greek tradition for their methods, which would surely have surprised that arch-experimentalist Aristotle.

[>]
 
objects move through the air
See Galileo's
Dialogues Concerning Two New Sciences.
The "two new sciences," by the way, were the resistance of solid bodies to breaking, and a treatment of all forms of motion.

[>]
 
at exactly the same moment
Contrary to legend, he didn't actually do this from the tower of Pisa.

[>]
 
an equivalent amount of water
He was too high by a factor of two, but it was still surprisingly close.

[>]
 
ceased to weigh anything at all
This idea originated with Aristotle in the fourth century B.C. and had persisted ever since. For once in his life Galileo was trapped in the wrong by sticking to received wisdom instead of thinking for himself.

[>]
 
Torricelli took a three-foot glass tube
Though it's still not clear exactly who performed the experiment that was to become famous, Torricelli probably asked his close friend, and fellow-disciple of Galileo, Vincenzio Viviani, to commission the apparatus and do the actual deed.

[>]
 
quarter and a finger more
Opinion is still divided on who came up with the idea of using mercury—it could have originated with Torricelli, or come from Viviani or even Galileo himself. In one copy of his
Dialogues,
after the part about the limited height to which water can be drawn up by a suction pump, Galileo seems to have dictated some margin notes to Viviani to the effect that other liquids should show a similar effect but to a lesser or greater height depending on the relative weights of the liquids, and he specifically mentioned wine, oil, and quicksilver. See Middleton,
The History of the Barometer,
p. 20.

[>]
 
mercury up into the tube
Middleton,
The History of the Barometer,
p. 24.

[>]
 
as inspiration for his most famous book
Another of Boyle's pieces, "Upon the Eating of Oysters" describes how two fictitious friends discuss the unfairness of regarding other nations' customs as barbaric and yet failing to see how outsiders might view one's own habits: "We impute it for a barbarous custom to many nations of the Indians," says one, "that like beasts they eat raw flesh. And pray how much is that worse than our eating raw fish, as we do in eating these ... oysters whole, guts, excrement and all?" In reply, his companion says: "you put me in mind of a fancy of your friend, Mr. Boyle" and goes on to describe Boyle's desire to write a short romantic story set in some South Pacific Island, governed by rational utopian laws, and how a native of those islands could travel throughout Europe and return home with bemused descriptions of our own strange, extravagant customs. Though Swift never acknowledged the debt, this could well have been the image that inspired
Gulliver's Travels.
Quoted, for example, in More,
The Life and Works of the Honourable Robert Boyle,
p. 158.

14 
enlightening rather than money-making
Pilkington,
Robert Boyle, Father of Chemistry,
p. 138.

[>]
 
he wasn't far off
This is about 3,750 million million tons, compared to the 5,600 million million tons quoted in Lyall Watson,
Heaven's Breath
(London: Hodder and Stoughton, 1984), p. 22. In 1648, Pascal had also persuaded his brother-in-law to take the quicksilver bath and glass tube up and down a mountain, to show that air weighs less at higher altitudes. Pascal's brother-in-law managed this with great success, though it can't have been easy to juggle the awkward contraption of bath, tube, quicksilver, and all at the top of the 4,800-foot Puy-de-Dôme, where he repeated the experiment five times, "once under cover in the little chapel which is there, or out-of-doors, once in a sheltered place, once in the wind, once while the weather was fine, and once during the fog and rain which came up now and then."

[>]
 
It wasn't easy
Boyle suffered from ill health for much of his adult life, but he responded to it in typically practical fashion. To protect himself from chills he had commissioned a range of cloaks to suit every possible variation in the weather, and before he went out he decided which one to wear by consulting a recently invented instrument known as a thermometer.

[>]
 
a height of 29½ inches
Actually this wasn't quite what Boyle had expected. Torricelli had reported that the mercury remained some 26 or 27 inches above the surface, rather than 29½. If the mercury was being held up by the downward weight of the atmosphere, why should there be such a difference? After all, exactly the same blanket of air was pressing down on both England and Italy. Could there be some problem with the apparatus, or, worse still, the theory? Before Boyle could toy with too many alarming ideas along these lines, he discovered that the answer was more to do with lack of intra-European coordination than any misbehavior of the atmosphere. "Our English Inches," he noted with relief, "are somewhat inferior in length to the digits made use of in Foreign Parts."

[>]
 
toward the box waiting below
The mercury never quite dropped to the level in the box because the pump couldn't quite succeed in extracting all the air. There was always a leak here or there, no matter how clever Hooke's design. But it fell quite far enough to satisfy Boyle, and ultimately the rest of the world.

20 
one of the world's first true scientists
He did however have an unfortunate tendency to overdose his descriptions. Why, after all, use one word when thirty would do? You could imagine him, dictating to his hapless secretaries, his sight too clouded to write for himself but his mind racing with ideas, determined to leave no room for error or doubt, and another thing, and another thing, and I must remember to mention yet another. An individual sentence would often contain well over one hundred words.
For instance, from the introduction to
New Experiments Physico-Mechanical Touching the Spring of Air,
here is Boyle's explanation for why he decided to study air (Check out the second sentence—it has 121 words!):
"I am not faintly induced to make choice of this subject by these two considerations: the one, that the air being so necessary to human life, that not only the generality of men, but most other creatures that breathe, cannot live many minutes without it, any considerable discovery of its nature seems likely to prove of moment to mankind. And the other is, that the ambient air being that, whereto both our own bodies, and most of the others we deal with here below, are almost perpetually contiguous, not only its alterations have a notable and manifest share in these obvious effects, that men have already been invited to ascribe thereunto (such as are the various distempers incident to human bodies, especially if crazy in the spring, the autumn, and also on most of the great and sudden changes of weather) but likewise the further discovery of the nature of air will probably discover to us, that it concurs more or less to the exhibiting of many phaenomena, in which it hath hitherto scarce been suspected to have any interest. So that a true account of any experiment that is new concerning a thing, wherewith we have such constant and necessary intercourse, may not only prove of some advantage to human life, but gratify philosophers by promoting their speculations on a subject, which hath so much opportunity to solicit their curiosity."

[>]
 
acts in every direction
Boyle also discovered the law that was famously named after him, which states that if you squeeze any amount of air into a smaller volume, the pressure goes up. Squeezing air into a higher pressure also affects the temperature that water can boil. In the rarefied air at the top of Mount Everest, water boils at around 160 degrees Fahrenheit, which is why it's impossible to make a decent cup of tea there. The reverse is true as well—at higher pressures, water boils at much higher temperatures. This is the principle behind the pressure cooker, which was invented by one of Boyle's contemporaries, Denis Papin, in 1682. The gentlemen of the recently created Royal Society in London had supper made in one, which, they wrote afterward, "caused much mirth amongst us and exceedingly pleased all the company." See
Robert Boyle's Experiments in Pneumatics,
edited by James Bryant Conant.

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