books and arts Getting it off the ground Celebrating the centenary of controlled, powered .

The and the that learning to fly was different to the art and sudden gusts by hills, trees and so forth”. Invention of the Aerial Age of creating a successful machine, and set This insightful statement shows that he visu- by Tom Crouch & Peter L. Jakab, out to do both, or, in Wilbur’s words, “to alized the as a smooth, ideal flow, until National Geographic Books: 2003. 256 pp. escape accident long enough to know how it was perturbed by obstacles. This meteoro- US$35, Can$55 to avoid accident”. logical requirement took the brothers to Wings of Madness: Alberto It is impossible to know exactly what each Kitty Hawk, on an outer bank of the North Santos-Dumont and the Invention of the Wright brothers contributed to the Carolina coast where, during experimental of Flight venture, so close were they in everything. sessions in 1900, 1901 and 1902, they devel- by Paul Hoffman But of the two,Wilbur, who was destined for oped their wing-warping gliders until they Fourth Estate: 2003. 384 pp. £10.99 Yale before suffering some strange neuras- could fly smoothly and consistently. Hyperion: 2003. 369 pp. $24.95 thenic breakdown, seems to have been the To design the wing they also collected Andrew Nahum more analytical. It was Wilbur who wrote and collated data from Lilienthal and from of observing the flight of buzzards, and that their own wind-tunnel experiments on wing A hundred years ago this week, Orville and “they regain their lateral balance, when camber, coefficients of lift and drag, and Wilbur Wright made the first controlled, partly overturned by a gust of wind, by a the movement of centre of pressure with powered flight in a heavier-than air torsion of the tips of their wings”. This changing incidence. Their analysis indicates machine. By then it was becoming accepted observation translated into what was per- considerable mathematical ability for boys that the idea of controlled flight might not haps the Wrights’most notable achievement: who left school at 17, and is a remarkable be so fantastical after all. The scientific the realization of the importance of control tribute to the American public education analysis of air and flying machines had in the roll axis. Their contemporaries, in system. At the same time they developed begun to be taken seriously in the the nine- contrast, thought that adequate control and their piloting skills and their understanding teenth century by engineers and scientists steering could be achieved purely by an of aircraft control so that,in the 1902 season, such as Gustave Eiffel, Samuel Pierpont elevator (pitch control) and a rudder (yaw they were able to complete more than 700 Langley and Hiram Maxim. control). The Wrights, however, understood successful glides, returning to Dayton to With the exception of Otto Lilienthal, that successful turns actually require the build an engine and attempt controlled, who flew his hang-gliders repeatedly, few aircraft to bank, using a proportion of the powered flight. None of their contempo- realized how capricious the air is. Although lift force to initiate and sustain the turn. raries made such persistent progress to there was much debate about the correct Wilbur’s systematic nature also led him to airmanship or developed full, balanced, expression for the resistance of the air, enquire about average wind speeds around three-axis control (of pitch, yaw and roll) which would determine wing lift, the more the United States. He reasoned that because until the Wrights finally demonstrated this immediate issues of pitch stability (control- “it is necessary to move through the air at 15 publicly in 1908. ling movement up and down), balance or 20 miles an hour in order to obtain sup- The excellent book by Tom Crouch and and control determined how long a ‘flight’ port,it is safer to practice in a wind,provided Peter Jakab is one of the first to speculate on lasted before the almost inevitable crash. this is not too much broken up into eddies the brothers’ mentality, their home life and How many seconds this took seems rather unimportant now, but it still receives the attention of many partisan enthusiasts determined to prove that Richard Pearse in New Zealand, Langley in Washington, the German–American Gustavus Whitehead, or Clement Ader in France flew, or even ‘could have flown’,before the Wright brothers. HULTON-DEUTSCH/CORBIS The reason for the Wright brothers’ success was that they combined in their joint enterprise the best empirical skills of Yankee inventiveness, intelligent observation and a scientific, or at least systematic, investi- gation into flight. Furthermore, as cyclists and bicycle-makers, they understood the importance of piloting. They sensed, in a way that almost no other flight pioneer except Lilienthal and the engineering scientist did,that a successful flying machine would not spring from the drawing board like a steam ship, ready to plough the aerial ocean. They knew that a flying machine might be successful but would still be nervy and treacherous, subject to the air currents of the moment. A bicycle might be an excellent machine, but the Trial and error: not all of the Wright brothers’ test using gliders were entirely successful. learner might still fall. They appreciated

NATURE | VOL 426 | 18/25 DECEMBER 2003 | www.nature.com/nature © 2003 Nature Publishing Group 765 books and arts the source of their originality. It contains which caused him to take his own life, was his flippant title, of confronting the tide of a generous ration of the wonderful photo- seeing the use of aeroplanes in the Brazilian irrationality in what is in effect a manual of graphs taken by the Wright brothers of their revolution of 1932. His last recorded words scientific reasoning. gliding experiments, and forms an engaging are said to have been: “I never thought my His method, originating in his earlier account of these epochal events. However, invention would cause bloodshed between book Nine Crazy Ideas in Science, is to test those wanting more depth must go to the brothers.What have I done?” I eight quite diverse propositions, extending two authors’ earlier books: Tom Crouch’s Andrew Nahum is senior curator of the from the unquestionably absurd (telekinesis, The Bishop’s Boys (W. W. Norton, 1989) and Aeronautical Collection at the Science Museum, or moving matter around by thought Peter Jakab’s Visions of a Flying Machine Exhibition Road, London SW7 2UD, UK. alone) to the probably valid, such as a part (Smithsonian Institution Press,1990). for genetic factors in determining sexual The aviator and celebrity Alberto Santos- inclination. He grades these on a scale of Dumont continues to puzzle and intrigue, ‘flakiness’:zero flakes implies that the propo- but many details of his life have been sition may well be true, and four flakes that obscure, his own book My Airships being A healthy draught it is unarguably nonsense. My dictionary one of the few sources of information. So defines ‘flaky’ as “adj. eccentric, crazy”, but Paul Hoffman’s Wings of Madness is a of scepticism this is not altogether what Ehrlich means by much-needed and long-overdue account. It Eight Preposterous Propositions: it; he conceives it as “lacking in empirical concentrates more on Santos Dumont’s life From the Genetics of evidence or internal consistency”, thereby than on the details of his flying machines. Homosexuality to the Benefits distinguishing it from his ‘crazy ideas’ in This fabulously rich Brazilian coffee tycoon of Global Warming science, some of which (like practically all of settled in Paris and took his first free by Robert Ehrlich Kuhn’s ‘paradigm shifts’) could be true. balloon flight with a professional balloon- Princeton University Press: 2003. 360 pp. Ehrlich’s longest chapter is devoted to maker in 1897, proving his scientific creden- $27.95, £18.95 the weighty question: “Should you worry tials by ascribing the extra effervescence Walter Gratzer about global warming?”After an impeccably of the champagne he took aloft to the neutral analysis of the passionate opinions high altitude. He soon progressed to small, A little way into Robert Ehrlich’s assault on on either side,Ehrlich awards it a (judiciously light airships, initially using the remarkably obfuscation and unreason, your appalled qualified) ‘one-flake’ rating — in other light internal combustion engine developed eye will light on a table which reveals that words, a negative answer to the question for the De Dion-Bouton tricycle. Santos- more than a quarter of the population of could just about be entertained. A strength Dumont became a popular figure as he the United States believes in witches, 41% of Ehrlich’s treatment is that he approaches dashed and sometimes crashed around Paris, in possession by the devil, fully a half in the truly preposterous theses — telekinesis often demonstrating remarkable control and extrasensory perception (ESP), and no less and the eclipse of evolution by “intelligent mooring the craft outside his apartment on than 45% are in no doubt that extraterres- design” — with a straight face. His reasoned the Champs-Élysées. trial beings have been stalking the Earth. demolition of the evidence for these aber- By 1906, Santos-Dumont, stimulated by (The physicist Leo Szilard said so too, but rations is vastly more effective than the the move among French aeronauts to better added that they are called Hungarians.) red-eyed apoplexy that seizes the average what they had heard of the Wrights’ flight, Worse still, even among the beneficiaries scientist at their mere mention. had built a heavier-than-air craft. The of a college education, only 16.5% are pre- But it is the final two chapters that I found diminutive Santos-Dumont stood in the pared to concede that Homo sapiens is a the most compelling. Ehrlich is at his most vehicle as it made a wallowing 240-metre product of evolution, unaided by the hand incisive on the placebo effect, and on the flight in the Parc de Bagatelle. This public of God. recent assertion in a widely publicized paper flight attracted media attention but the craft Such dense fog between the ears is invari- that its extent has been grossly exaggerated. was barely under control and made no ably linked to an inability to grasp that The arguments hinge, for the most part, on contribution to heavier-than-air flight. improbable events are merely manifes- the interpretation of statistics,which Ehrlich When Wilbur Wright came to France in tations of the rules of chance, and not of manages to make accessible to all who will 1908,Santos-Dumont seemed put out by the divine intervention. Oscar Wilde under- make the effort. Only at one point, isolated adulation that the American received, and stood this ingrained disorder of the human in a box from which innumerate readers began to show the beginnings of the depres- intellect: “Man can always believe the can avert their eyes, does he set out the sion and mental problems that would sub- impossible, but man can never believe the mathematics in full. sequently dog him. He became obsessed improbable,” he observed. Ehrlich has set He makes a powerful case that many, and with new uses for aeroplanes.The final straw, himself the heroic task, concealed beneath especially psychotropic, drugs which make extravagant profits for the pharmaceutical industry are ineffective or worse. He un- Let it snow covers the weaknesses in conventionally It is said that no two snowflakes are identical. Each contains about a billion billion water molecules, designed double-blind trials and, both here so the number of possible configurations is enormous. These photographs by Patricia Rasmussen and in his final chapter (“Should you worry are from The Snowflake: Winter’s Secret Beauty by Kenneth Libbrecht (Voyageur Press, $20). about your cholesterol?”), he expatiates on the lax standards by which the industry is now regulated, and the way in which the once-proud US Food and Drug Administra- tion has been emasculated.What is especially striking is the low confidence limit (P<0.05) considered adequate to establish the efficacy of a new drug in clinical trials — a level that is perhaps acceptable in sociological research, but is generally considered risible in the exact sciences.

766 © 2003 Nature Publishing GroupNATURE | VOL 426 | 18/25 DECEMBER 2003 | www.nature.com/nature