Alfred Wegener

by Mott T. Greene

LINDENBERG, 1905–1906

  The balloon of experience is in fact of course tied to the earth, and under that necessity we swing, thanks to a rope of remarkable length, in the more or less commodious car of the imagination, but it is by the rope we know where we are, and from the moment that cable is cut we are at large and unrelated.

  HENRY JAMES (1909)

  The chief danger attending ballooning lies in the descent.

  Encyclopedia Britannica (1910)

  On 1 January 1905, Dr. Alfred Wegener joined the scientific staff of the Royal Prussian Aeronautical Observatory, a complex of buildings rising rapidly on a 28-hectare (~70-acre) tract in the middle of some wheat and barley fields 60 kilometers (37 miles) southeast of Berlin. The observatory was a little to the north of the main rail line, though served well enough by a station and siding a kilometer away in Lindenberg.

  Of course, Alfred wasn’t really Dr. Wegener yet, and would not be until the publication of his dissertation in March, but then the observatory wasn’t really an observatory yet either. It had been under construction since June 1904, and while the pace of the work had been aided by an exceptionally dry summer, the scientific station was still far from complete. The headquarters building, the staff residence, and the director’s house were finished, but the machine shops, the hangars, a powerhouse for the diesel generators and the massive array of electrical batteries, the central steam-generating plant, the dry ice machine, the large electrolytic apparatus for obtaining hydrogen and oxygen, and many other utilities and support buildings were in various stages of incompletion; the full scientific program could not begin until April.1

  Alfred’s appointment, even if only as Technische Hilfsarbeiter (technical assistant), was his portal to a new career in a new science, and it was also the first real step toward an independent adult life. Both were welcome, and the latter perhaps overdue for a twenty-four-year old man who had finished his doctoral degree and the bulk of his military service without ever residing more than a few kilometers from his parents—if one excepts the Heidelberg semester and a summer in Innsbruck. The tether to home and family was still secure, but it was time to pay it out a little.

  Alfred was clearly pleased with the position, made possible by the accelerated shift from astronomical to meteorological subjects in the final year of his doctoral work at Berlin and by Bezold’s recommendation. He had no regrets about taking his degree in astronomy and recognized that it was actually a form of security, since prospects for academic employment in meteorology were the poorest of all the fields of physical science. Indeed, many academic scientists and most physicists doubted that meteorology had enough theoretical content and practical rigor to qualify as a physical science at all. In consequence, there were only two real university professorships of meteorology in Germany and Austria, created for distinguished individuals who had beaten the odds that “a physicist who goes into meteorology is lost”—the often-repeated opinion of the physicist Friedrich Kohlrausch.2 There was Wegener’s own professor at Berlin, Wilhelm von Bezold, holding the first and only professorial chair of meteorology in the whole German Empire—and this, in part, as a courtesy appointment befitting his status as head of the Prussian Meteorological Institute. There was also the chair in meteorology and geophysics created for Julius Hann (1839–1921) at Graz in Austria, which persisted after Hann moved in 1900 to Vienna for the chair in cosmic physics.

  With the exception of Bezold and Hann, all the other great meteorologists in German-speaking academia worked in nonacademic positions in state-supported institutes: Wladimir Köppen (1846–1940) at the German Marine Observatory in Hamburg, Hugo Hergesell (1859–1938) at Straßburg, and Richard Aßmann (1845–1918), Wegener’s own superior officer at the Lindenberg Observatory. Under the direction of these institute leaders and section chiefs were a large number of workers variously styled “collaborators,” “assistants,” and “helpers.” These were modest employments (in terms of compensation and job security) but often filled by scientists of international distinction, such as the great balloonist Arthur Berson (1859–1942), Aßmann’s collaborator for twenty years at Berlin and then Lindenberg. The list also includes the Austrian Max Margules (1856–1920), the great theorist of atmospheric energy processes, who never got farther than a staff position as an assistant at the Vienna Zentralanstalt für Meteorologie and took early retirement in 1906 on a minuscule pension, despairing of better employment.

  In England, Russia, and Scandinavia the situation was much the same. A meteorologist as distinguished as Nils Ekholm (1848–1923), a collaborator of Svante Arrhenius and a great polar traveler, climatologist, and student of weather forecasting, worked as an assistant at Uppsala and Stockholm from 1876 until 1898 and then supported himself as a mathematician for a life insurance company from 1898 until 1913, when, at the age of 65, he finally obtained the professorship that went along with the directorship of the Meteorological Institute in Stockholm.3

  Still farther from the ranks of university and government posts there were independent scientists like the French pioneer of upper atmospheric research, Léon Teisserenc de Bort (1855–1913), and his American counterpart and friend A. Lawrence Rotch (1861–1913). They combined personal means and private sponsors (including, in Teisserenc de Bort’s case, Prince Albert of Monaco) to erect independent institutes where they pursued their own programs of research.

  Wegener’s job as a technical assistant was, therefore, not necessarily the sort of self-limiting position we now call a “postdoctoral” appointment, nor was it realistically a stepping stone on the path to the security and status of the sort of employment that the Germans called pensioniert (pensioned). Yet, notwithstanding its clear limitations and the almost nonexistent chances for advancement, it was at the time a sort of minor miracle: a real, immediately available scientific employment in meteorology, in a completely new area of scientific study—trying to describe and understand the vertical structure of the atmosphere.

  There was more good fortune at hand for Alfred: the only other technical assistant hired as of the first of the year was his brother Kurt, who had just taken his degree in meteorology at the Physical-Technical Institute in Charlottenburg. Here was a chance to continue to work together toward plans and goals that, for the moment at least, seemed to be converging. They had hiked, climbed, and studied together in the Alps, done their military service back to back, and passed every university holiday either touring or relaxing at die Hütte with Tony and their parents.

  Now they were to share the beginning of their scientific careers, as well as new, modern, clean, spacious, and even luxurious accommodations on the third floor of the headquarters building—with indoor plumbing, hot and cold running water, and a living room and bedroom of their own. On the second floor were the scientific workrooms, and on the ground floor, in addition to the administrative center, were a dining room and a Rauchzimmer (smoking room), where they could, respectively, be served their meals by the cooks and waitstaff and indulge an already extravagant fondness for tobacco. They could, of an evening, enjoy a quiet beer here with colleagues, discussing their work, with their own steins kept on a shelf like any neighborhood tavern.

  Alfred and Kurt were happily oblivious to the disarray and general confusion caused by construction at Lindenberg. They had spent most of their lives in Berlin surrounded by massive and noisy construction projects, and it was nothing new to have everything torn up and nothing finished. Moreover, the station rising in the middle of the sparse landscape had an almost expeditionary character and excitement to it.4

  Lindenberg was to be the main German center for aerology—the investigation of the three-dimensional structure of the atmosphere by sending up (to altitudes of several kilometers) meteorological recording instruments via “captive” balloons and kites, tethered to the ground by steel cables. Aerologists also sent aloft to much greater altitudes “free balloons” (designed to parachute back to earth with their instrument packages). Finally, the scientists went aloft themselves i
n manned balloons capable of carrying several investigators and a large and varied array of sensing and recording devices. It was specifically to pursue these aerial investigations that the Wegener brothers had been recruited. As the technical assistants, they were to work directly with the “observer,” Arthur Berson, and with the director of the station, Aßmann, in conducting flights of these experimental aircraft and the even more experimental instruments they carried. Supported by a staff that was soon to number almost fifty technicians, machinists, engineers, clerks, and cooks, they were to be an atmospheric science counterpart to the scientific staff at German Marine Observatory in Hamburg, which had been founded decades before as the principal station and clearinghouse for German oceanographic and marine meteorological research.

  The unprecedented sums of money available for this new scientific station were a result of direct royal patronage. Kaiser Wilhelm II aspired to be a patron of science and technology on the pattern of his friend Prince Albert of Monaco—long a patron of oceanography, meteorology, and marine biology. The kaiser had an interest in aeronautics and meteorology, intensified by his general staff’s conviction that long-distance and controlled flight was imminent and would have important military consequences.

  Lindenberg Observatory was intended to be the aeronautical version not just of an oceanographic station but also of a research vessel, carrying a crew to study the “ocean of air.” Aerology was borrowing terminology and methods from the preexisting scientific and technical field of oceanography—just as aeronautics was busily borrowing the vocabulary of merchant shipping. The first flying machines—the zeppelins—were “air-ships,” and they landed and took off from “air-ports.” They had captains and a crew, as well as pilots and navigators on the “flight deck” or in the “cockpit” wearing nautical-style uniforms and gold braid. They measured their speed in knots (nautical miles per hour), and they had a fore and an aft, port and starboard sides, and soon also passenger cabins and cargo holds. The choice of terms was obvious and deliberate, but it was also apposite to a degree that makes it a pleasure to reflect on even a century later, when we are long accustomed to it.

  Of course, the metaphor of Lindenberg as a research vessel had its limitations, for ocean-going ships study the ocean as they move about, while this “vessel” was anchored permanently in Lindenberg; but what matter if the ship move over the water, or the water under the ship? It is actually more convenient to have an observation platform in one place, and not always to have to subtract or add the station’s direction and velocity to calculations of currents and flows, as one must do on a moving ship. In this way Lindenberg’s situation was also like that of an astronomical observatory, with the sky passing in review each night. There was plenty of weather passing over Lindenberg and consequently a great many interesting atmospheric phenomena arriving overhead to investigate.

  The Work of the Observatory

  The heart of the observatory, and of Wegener’s work there, was the Windenhaus, a large, octagonal metal and glass gazebo standing on the highest point of the station grounds (127 meters [417 feet]) surmounted by a cupola containing three 1,500-watt beacons visible at night for 20–30 kilometers (12–19 miles).5

  The Windenhaus itself reflected Richard Aßmann’s perfectionism and love of devices. It was mounted on a rotating platform, supported on four rollers seated on a circular iron rail. Inside the building was the Winde, the large motorized winch with its gearboxes and electrical motor capable of paying out 20,000 meters (65,617 feet) of wire. Inside the Windenhaus was a workstation holding the station logbook, with a chronometer and an anemograph that recorded the wind speed and direction from the anemometer atop the cupola.

  The workstation also featured another of Aßmann’s myriad instrumental monotypes: an aspiration meteorograph on a design he had conjured twenty-five years earlier in Berlin. Air was pulled into the instrument by an electric fan through a pipe that penetrated the wall on the windward side of the building. As the air passed through the pipe at 7 liters (1.8 gallons) per second, compact instruments (of Aßmann’s design or modification) measured the barometric pressure, air temperature, and relative humidity and recorded these on a scrolling sheet of graph paper which could hold a week’s observations.

  The aspiration meteorograph served, before and after each flight of a balloon or kite from the Windenhaus, as a reference standard for the instruments and recording devices sent aloft. Before and after each flight, the scientist standing watch in the Windenhaus placed the kite or balloon meteorograph on a meter-long horizontal strut, fastened to the outside wall of the Windenhaus. This strut could be moved to whichever was the windward side, by virtue of regularly spaced mounting brackets on the exterior walls. It was also fitted with an electrical lamp so that readings could be taken at night. Once mounted, the instrument destined to go aloft was allowed to run for a set time to measure and record the temperature, humidity, and atmospheric pressure, while ventilated by an electrically driven fan. This procedure served to calibrate the instruments relative to a reference ground station and to provide a correction factor to add or subtract from the recorded aerial data.

  The scientific staff, Wegener and his colleagues, calibrated the tiny anemometers in the instrument packages sent aloft using a “Scirocco-Ventilator” in the laboratory—a variable-speed wind generator. They also regularly checked barometers and barographs in a vacuum chamber and recorded each instrument’s peculiarities and standard errors. There were corrections for the corrections: Aßmann’s aspiration meteorograph could not help heating up in still air and strong sunlight, so it had to be corrected yet again, using a separate aspiration psychrometer, before, during, and after each flight. Moreover, all these readings had to be compared to the observed values in the Sun-shielded ground station that was the official meteorological station record of the Lindenberg Observatory.6

  Windenhaus (winch house) at Lindenberg, showing a tethered balloon ready for launch. Note the recording instruments trailing the balloon on the cable tether (here just above the roof line). From Richard Aßmann, Das Königlich Preußische Aeronautische Observatorium Lindenberg (Braunschweig: Friedrich Vieweg & Sohn, 1915).

  As scientific work, it was painstaking and even finicky, but it appealed to Wegener’s mechanical inclinations, his pleasure in collecting data, and his love of calculation, correction, and data reduction. It is no accident that all the great advances in aerology at this time were made by scientists with a love for instruments and instrument technology. Aßmann, Léon Teisserenc de Bort, and Hugo Hergesell all employed instruments they had designed and built, and each had a variety of instruments named after him. Much of the work of this new science was the struggle for every marginal increment of accuracy and durability in meteorological instrumentation, and each of the competing designers hoped that his instrument would become a professional standard.

  While at Lindenberg, Wegener’s principal employment was to help send these carefully calibrated instruments aloft seven days a week (holidays included) at set hours. The ambitious schedule included a flight from 7:00 to 10:00 a.m., one from 2:00 to 6:00 p.m., and one from 9:00 p.m. until midnight. At set times during the year “International Flight Weeks” meant the addition of a flight from 2:00 to 5:00 a.m. Once a month (usually the first Sunday) an instrument package went aloft for twenty-four hours of continuous observations.7 It actually took many years to reach these ambitious goals. In the sixteen months Wegener spent at Lindenberg, there were about 400 kite ascents and about 140 captive balloon ascents, with balloons going up every third day (on average)—with the frequency determined by the wind speed, or lack of it, since kites could not be flown in still air.8

  Meteorological kite flying was only a decade or so old when Wegener took it up at Lindenberg. An Australian scientist named Lawrence Hargrave (1850–1915), who designed and built model flying machines, had invented, around 1885, the kite design we now call a “box-kite,” characterized by a high angle of flight and great stability in the wind. P
art of the design was tinkering, but part was a result of advances in the theory of the optimal loading of sails for the great clipper ships that dominated Pacific commerce. Until the advent of wire for the standing rigging that held the masts stable, the rope rigging of such ships caught so much wind that it was extremely difficult to calculate the optimal size, position, and trim of sail. With the advent of thin-wire rigging, catching almost no wind, sail design and ship rigging jumped ahead, and by the later 1880s the theory of sail was beginning to be available in the technical literature. One fallout from this was kite design, since a kite is nothing but a sail or series of sails rigged on a wooden frame and tethered by a line to the ground.

  Scientific kite and balloon flying was a field that for several decades attracted both professional and amateur interest—the young Ludwig Wittgenstein (1889–1951), on his first trip to England in 1908, built and flew meteorological kites for the Kite Flying Upper Atmosphere Station at Glossop, near Manchester.9

  The Hargrave kite made aerology possible as a systematic enterprise, because it dramatically lowered the cost of sending instruments into the air. When reeled out on a cable and carrying the lightweight and immensely durable meteorograph designed by the American Charles F. Marvin (1858–1943), a Hargrave kite allowed precise meteorological observations to be taken and recorded at altitudes of several kilometers, day after day.

  It was, of course, possible to do this with free balloons, as Teisserenc de Bort had done for years at his own station at Trappes, in France. These were delicate, expensive things made of silk, kerosened paper, or goldbeater’s skin, a fabric made from strips of cured ox-gut glued together. All of these balloons were capable of carrying meteorographic packages of instruments up to 14 kilometers (9 miles) above the ground. When they reached a certain altitude or time aloft, a mechanical hook tore a strip from the balloon, transforming it into a parachute to return the instruments to earth. The instrument packs were marked with Teisserenc de Bort’s name and address, and he paid a substantial reward for their return.