by James Tobin
LANGLEY ADORED CHILDREN. When he visited the homes of friends with youngsters, he would take them on his knee and tell them fairy tales, “many of which he would improvise with wonderful tact to please the children.” Yet he never married. He was friendly with women, but apparently never became romantically attached to anyone. When the sun went down each day, the gaslight inside the house on the observatory hill burned only for him, alone in his chair with his books.
He read deeply and remembered, it seemed, practically everything. He read the great English novelists and German classics. He was fascinated by fairy tales, folklore, and ancient mythology. A prized possession was his collection of various editions of the Arabian Nights. He studied British and French history and biography. Later, in Washington, when Andrew Dickson White gave a series of lectures on the French Revolution, White was astonished at the learning that Langley’s questions revealed. “I particularly remember his minute and accurate knowledge of the comparative value of sundry authorities,” White recalled. “It was not merely that he had read works of importance in the history of the period . . . but that he had gone extensively into original sources, and especially into the multitude of memoirs.”
Though not a churchgoer, Langley thought deeply on questions of ultimate reality. He was “an ardent seeker of religious truth . . .” White said, “equally hostile to dogmatism against and in favor of received opinions.” He “loved to talk with men of positive religious views about their own beliefs, and took a deep interest in a Jesuit, or a Jew, or a Buddhist, or a Mohammedan, or, indeed, in any man who thought he had secured any truth and knew the way of life in this world or in the world to come.” An aide and friend at Allegheny said, “There was something reaching almost to the transcendental in his inner life.”
As the years passed, his work took him into deeper realms of the universe; his reading drew him into the fellowship of far-flung intellectuals, communing through the written word; and he became ever more a man unto himself, less likely to find companionship in Pittsburgh than when he arrived in 1867. Yet he was burdened by “a strong craving for real society,” a friend said, “by which he meant intercourse with people of diverse minds and knowledge, all of whom might give him that intellectual companionship for which he hungered.” He found few friends among his faculty colleagues, perhaps because he considered them beneath his intellect, perhaps because they continued to resent his high pay and privileges. He attended meetings of Pittsburgh’s medical society just to be able to talk with professional men who knew the language of science. On Sunday evenings he would descend his hill and trudge to the back room of a drugstore because a half-dozen souls gathered there to talk about books. To his friend Charles Sanders Peirce, the eminent Johns Hopkins philosopher, who had visited Langley in Pittsburgh, he wrote: “You have seen for yourself how far it is from the companionship a student of science wants; and you will understand what I mean in saying that I am in that respect out in the cold, and would on that account willingly warm myself once or twice at your Baltimore fire.”
As factories edged closer to his hilltop, their smoke obscuring the skies, Langley found Pittsburgh more and more stifling. In an 1884 report to the community, he frankly asserted that the observatory lacked “almost every thing outside of its actual apparatus that the ordinary resources of American civilization would provide for it in any large American city but Pittsburgh.” Its work—his work—had gone forward despite “a constant struggle with poverty,” an assertion that no doubt caused eyes to roll among his lesser-paid colleagues. “There are not only no museums of art, no libraries of reference, no collections of scientific material, but in general, none of those aids to the investigator which are to be found in so many younger and smaller places.”
He fled as often as he could. He went to Boston to see his mother, his aunt, and colleagues in the sciences, especially E. C. Pickering, a Harvard astronomer who became a close friend. During summers in Europe, often with Pickering in tow, he visited observatories, met with foreign colleagues, and acquired a taste for fine food and wine. As his own publications mounted, European astronomers increasingly knew Langley’s name and reputation. But he cringed whenever he had to explain where he came from. Once a reporter asked him if European scientists didn’t pity Langley for being stuck under Pittsburgh’s smoky skies. “In the astronomical circles of the Old World,” he replied, “it is often the case that the existence of Pittsburgh itself is hardly known, and the Allegheny Observatory is thought, from its name, to be located somewhere on the summit of the Allegheny Mountains.”
Friends on other campuses tried to find him a position that would better fit his growing reputation and satisfy his desire for comradeship. C. S. Peirce told Daniel Coit Gilman, president of Johns Hopkins, that Langley was the right man to direct the great observatory that Gilman wanted to build. Langley would be “a great addition to the university,” Peirce advised, “widely known not only as one of the very first men in the New Astronomy but also as a very charming and cultured person.” But the Johns Hopkins observatory remained unbuilt. In Cambridge, friends spoke of Langley as the obvious successor to his old superior, Joseph Winlock. But someone else was chosen. He was elected president of the American Association for the Advancement of Science, a post of immense prestige. But he walked the streets of Pittsburgh unrecognized amid people who had no inkling that such a thing as the solar spectrum existed, let alone why anyone would want to measure it.
As the 1880s passed, Langley could not have escaped the sense that his chance to become one of the historic figures of his own field, rather than merely an accomplished practitioner, was slipping away. The developing science of astrophysics was becoming too sophisticated for any scientist who, like himself, lacked proper training in differential equations and calculus. He said he was at best “a learner” in the higher mathematics, which he found a source of both wonder and frustration. Once, he instructed some aides to calculate the equation for a curve, and when they did the work “in a decidedly roundabout way . . . covering many pages with mysterious-looking formulae and equations . . . it was interesting to note the almost reverence with which he afterward turned these pages, really impressed by what looked so profound, and which he did not understand.”
In a moment of humility he confessed to a friend: “I know nothing about chemistry and little about chemical physics,” and, “I have never been able to flatter myself that I could reach any eminence in . . . mathematics.” When he vented his irritation, saying math was inferior to the direct telescopic observation that he did best, another astrophysicist issued a stinging put-down: “Professor Langley . . . shares the views of not a few, possessing like himself marked aptitude for experimental research, but seeming to become actually irritated when physical matters are dealt with in the only way in which they can be satisfactorily analysed. . . . No physicist, certainly no astronomical physicist, can successfully deal with the problems which come before him, without a mastery of at least the elementary methods of mathematical analysis—as the differential and integral calculus, the treatment of differential equations, the calculus of variations, and the like.”
If these were the keys to the cosmos, Langley knew he did not possess them.
• • •
IN AUGUST 1886 Langley caught a train for the annual meeting of the American Association for the Advancement of Science in Buffalo. The association had been founded in the 1850s to promote the highest standards of scholarly investigation and to “repress charlatanism.” These were the elites of American science, jealous of their reputation as high-minded truth-seekers, ever watchful for cranks and goofball theorists who might undermine public support for science. Still, promising amateurs occasionally were allowed to speak. Among the amateurs on the program at the 1886 meeting was an Illinois farmer and self-taught ornithologist, Israel Lancaster. He claimed that birdlike devices of his own design could stay aloft for as long as fifteen minutes. On a larger scale, he said, such devices could carry a man.
Lancaster’s first talk turned into a circus. Scientists laughed at his claims. Five days later the attendees jammed the room for Lancaster’s second talk, advertised as a demonstration of artificial birds. But Lancaster showed up with only a device to show the effects of air pressure on plane surfaces. This caused “great disappointment” among his listeners, The New York Times reported, and many “questions from the incredulous audience.” When Lancaster insisted a flying model could be constructed in minutes, one skeptic challenged him to do so on the spot. Another rose to offer one hundred dollars for a flying model; a third offered one thousand dollars; and this session, too, dissolved in noisy laughing and jeers.
Langley was in the audience, but he didn’t laugh. The farmer’s presentation had reminded him of the hawks he had watched in his childhood, and now, “I was brought to think of these things again, and to ask myself whether the problem of artificial flight was as hopeless and as absurd as it was then thought to be.”
LANGLEY KNEW “the whole subject of mechanical flight was . . . generally considered to be a field fitted rather for the pursuits of the charlatan than for those of the man of science.” If he chose to work on it, he would risk his reputation as a serious investigator, and if he failed, as every other experimenter had, he could count on outright ridicule, perhaps even the dismissal of all his legitimate work in astronomy.
So he began cautiously. He would attempt a single step in the direction of artificial flight—“Not to build a flying-machine at once, but to find the principles upon which one should be built.” Isaac Newton had believed that artificial flight would require power beyond the capacity of man. This had been true in Newton’s own time, perhaps, before the revolution in mechanical power, but was it true still? Langley decided he would try to determine precisely how much power was required “to sustain a surface of given weight by means of its motion through the air.”
In the yard of the Allegheny Observatory he directed the construction of a large machine called a whirling table, or whirling arm, for swinging winglike surfaces and stuffed birds in circles. The purpose was to measure the lift exerted by surfaces of various sizes and shapes. A steam engine drove the arm round and round at speeds of up to seventy miles per hour.
In one key test, Langley suspended a simple, one-pound brass plate by a spring from the end of the whirling arm. The weight of the plate, of course, caused the spring to extend a little. Then he set the arm in motion. By Newton’s reckoning of centrifugal force, he noted, “It might naturally be supposed that, as it was drawn faster, the pull would be greater.” But in fact, “the contrary was observed, for under these circumstances the spring contracted, till it registered less than an ounce. When the speed increased to that of a bird, the brass plate seemed to float on the air; and not only this, but taking into consideration both the strain and the velocity, it was found that absolutely less power was spent to make the plate move fast than slow.” This result he found “very extraordinary,” not to say paradoxical. After all, in any other form of transportation, from the oxcart to the locomotive, it was easier—that is, it required less power—to go slow than to go fast. But in the air, the experiment now suggested, the reverse was true.
To make sense of this puzzle, Langley remembered scenes from childhood. He thought of a stone skipping across water. Moving fast, the stone bounced off the water’s surface, but when the stone’s momentum slowed, it penetrated the surface and sank. He thought of a skater on the thin ice of a pond in spring. If the skater slowed down or stopped, he would plunge through. But if he maintained his speed, he could skim safely across. Thin ice might not hold much weight, but like every other substance in nature, it possessed a certain amount of inertia—that is, it resisted anything trying to push it out of its place. The same must be true, Langley said, of “the viewless air. Like thin ice on a pond, the air could hold up a moving object, but only if the object moved fast enough.” Langley deduced that speed was the key to human flight.
IN THE FALL OF 1886, just as Langley was beginning his study of aerial locomotion, the regents of the Smithsonian Institution were considering who should succeed the great naturalist Spencer Baird as secretary of the Smithsonian. Baird, at sixty-three, was complaining of exhaustion and a weak heart. Asa Gray, a distinguished Harvard botanist and an influential regent, wanted Langley to become an assistant secretary under Baird, with the understanding that he would move up upon Baird’s retirement or death. Gray spoke to his Harvard colleague, E. C. Pickering, asking him to sound out his friend in Pittsburgh.
Langley was surprisingly cautious. On the one hand, the overture exceeded his fondest hopes for recognition and intellectual companionship. Yet the actual job that Baird was offering Langley was assistant secretary for international exchange. This meant presiding over the Institution’s elaborate effort to distribute its publications around the world and to communicate with scientists and scholars. It was essentially a librarian’s job, and a demanding one. He wanted assurances that he could continue his scientific work. “I have no wish or ambition,” he told Baird, “to tempt me from giving most of my time to physical investigation—at least now, while I enjoy exceptional facilities for this, together with a freedom which I could not expect in any subordinate position.”
My professional life here [in Pittsburgh] is . . . a very pleasant one, in most respects, nor have I had occasion to leave the work of my predilection to increase my income. At the same time both my professional and domestic life here are exceptionally isolated, and I have felt the need of some change which would bring with it, along with society, new occupation, if that could be of a kind not wholly dissociated from my accustomed pursuits.
Baird said to come ahead; he could do his research. Langley made arrangements to continue as director of the Allegheny Observatory on a part-time basis, and left for Washington. Eight months later, Baird died, and the regents asked Langley to succeed him. He was inaugurated as the third secretary of the Institution in 1887.
EVEN AS LANGLEY was conducting the whirling-arm experiments, he was groping for a way to move beyond them—to construct a device that would fly by itself. By instinct and experience, he was an observer, not a theorist or designer. He needed something to observe, to gauge its behavior and make adjustments that might lead to a more promising next step. But the only things that actually flew were birds, and birds, he found, did not yield their secrets easily. The medium in which they operated—the ever-shifting air—was invisible. It was hard enough to track the movements of birds’ wings, harder still to understand them when he had no way of measuring the forces acting upon them. Now that he was in Washington, he had new means of investigation at his disposal. He examined birds’ anatomy, even the skeletons of pterodactyls in dusty Smithsonian storerooms. But it was no simple problem to reproduce the remarkable shape and flexibility of a bird’s wing, or its connection to the body. It was especially daunting to make a mechanism that would reproduce the “instinctive control of the wing,” which presumably allowed a bird “to meet the requirements of flight that are varying from second to second, and which no automatic adjustment can adequately meet.”
When he began in 1887, he was not yet familiar with the hand-held toy flyers that a young Frenchman, Alphonse Pénaud, had devised some years earlier—marvelous contraptions that had amused thousands of children around the world, including Wilbur Wright. (These were the “bats” Wright mentioned in his letter to the Smithsonian.) Though they stayed up no more than ten seconds or so, they were the first devices that ever kept their balance in the air. Langley needed something like them, if only to get some idea of what not to do.
One of his strengths—born of courage or sheer curiosity or some combination of the two—was a capacity to begin working in the face of an inexplicable and uncharted problem. He started from scratch. Still good with his hands, he constructed a series of hand-held devices similar to Pénaud’s. The first, vaguely resembling the shape of a bird, was “a light wooden frame with two propellers, each dri
ven by a strand of twisted rubber.” He built more than forty hand-launched models in all. He tried the early ones on the grounds of the Allegheny Observatory, the later ones on the green plain of Smithsonian Park. Clerks and scientists alike would peer out the windows at their leader; one said, “It was a very amusing sight to behold the dignified Secretary . . . rushing about with coat-tails flying, chasing and dodging the little toy planes.”
Model by model, adjustment by adjustment, the devices improved, but not enough. Pénaud had reported flights of up to fifteen seconds with his marvelous little toys, but Langley never could make a model stay up for more than eight seconds, or fly for more than one hundred feet. “No machine in the whole history of invention, unless it were this toy of Pénaud’s, had ever . . . flown for even ten seconds,” he said later, “but something that will actually fly must be had to teach the art of ‘balancing.’” To understand the principles underlying that art, he needed to observe a machine in sustained flight. But to put a machine in flight, he had to understand the underlying principles.
“SOMETHING THAT WILL ACTUALLY FLY MUST BE HAD.”
Two of Langley’s hand-held model aerodromes
There was only one route out of the paradox. If he meant to keep a machine in the air long enough to allow observation, he needed an engine much more powerful than a twisted strand of rubber. He knew power and speed were not sufficient, by themselves, to solve the puzzle of flight. “It is enough,” he wrote, “to look up at the gulls or buzzards, soaring overhead, and to watch the incessant rocking and balancing which accompanies their gliding motion to apprehend that they find something more than mere strength of wing necessary, and that the machine would have need of something more than mechanical power, though what this something was was not clear.” But as a beginning, he would have to concentrate on the task that was clear—to build an engine powerful enough to propel a weight through the air, yet light enough not to bring the craft crashing down. How to go up, how to come down, how to turn left and right—those problems, however essential, must wait. On vacations at Alexander Graham Bell’s magnificent estate overlooking the Bras d’Or Lakes in Cape Breton, Nova Scotia, Langley and his friend would spend hours on Bell’s houseboat, talking and speculating as gulls wheeled overhead. Once, after a long period of observing the birds in silence, the secretary exploded: “Isn’t that maddening!”