Alfred Wegener

by Mott T. Greene

  Sofia, Bulgaria

  Wegener wrote to Köppen in early August (his first letter to him since May) to tell him that he had been reassigned as commanding officer of the Central Meteorological Station in Sofia, Bulgaria, an appointment that would begin in September. Bulgaria had entered the war in 1915 on the German side and had used the alliance to pry territory away from Serbia (in Macedonia) and Greece. German and Bulgarian troops had also made significant inroads into Romania. The Central Meteorological Station in Sofia coordinated all weather data from stations in Turkey, Albania, the Black Sea, and the annexed portion of Romania, and it worked together with the Bulgarian Meteorological Institute to provide weather forecasts throughout the Balkans.

  Alfred was alternately resigned and enthused about the transfer; the press of administrative work in Jüterbog had prevented him from doing any science at all, and he hoped that he might be able to do some real scientific work in Sofia. His junior officer at Field Weather Station 12, Porstmann, had loaned him a volume of “Sunday Sermons,” by the secular humanist philosopher and Nobel Prize–winning chemist Wilhelm Ostwald. Ostwald urged an “energetic imperative,” using the second law of thermodynamics as a guide to personal conduct, maximizing energy and productivity. Wegener had found these “Sunday sermons” a little bit bland and colorless, if well meaning, and noted sardonically that, as director in Sofia, he would probably maximize “energy wasting.” He hoped that he would be able to off-load as many administrative duties as possible to his junior officers in order to make some time for his own work. He had already determined to have all the weather stations in the Balkans make measurements of atmospheric polarization, and he asked Köppen whether he had any suggestions for other systematic measurements. Here as elsewhere in his military service, he tried to do as much science as was possible, or rather not to miss a chance to do science in the context of the war work.93

  In mid-August he was rotated out of his command at Jüterbog and given home leave. It was not much of a vacation: Else and the family physician put Alfred on a ten-day diet of nothing but cottage cheese in order to cure his dysentery (it worked). His sickness in July and his rapid recovery in August made it clear to him and to Else how much he needed her care and solace, as well as how much he missed her. They talked about this in Marburg and determined that as soon as he could process the paperwork with his superiors she should come to Sofia and stay for as long as possible; Hilde would go to her maternal grandparents in Hamburg. The pretext was a sponsored program: “the advancement of friendship between the Bulgarian and German peoples.”94

  Wegener traveled to Sofia at the end of August and was immediately buried in work, learning the duties he would take up officially on 1 October. He was also charged to make a tour of his component stations, including those in Constantinople and on the Black Sea. Soon after his arrival, he realized that money would be a problem once again. He had to pay for his own lodgings, and a single room (even without breakfast coffee) cost 100 marks per month, larger than his monthly rent in Marburg for a full apartment. Though Marburg University had paid him two different stipends in the summer of 1917 and he had his captain’s salary, even with a 300-mark-per-month subsistence allowance, things were still bad.95

  If food was expensive, it was at least plentiful, and he told Köppen that he would soon be sending food to him in Germany, even though this was forbidden and treated as a black market activity. In fact, throughout his time in Sofia, Wegener superintended a very large network to obtain food and to send it in small packets, unlikely to be intercepted by the authorities, to the families of his subordinates in Germany. He would eventually turn an unused storeroom in the Meteorological Institute in Sofia into a sort of henhouse, where chickens and geese could be held and fed until someone was going back to Germany on leave, at which point the fowl could be slaughtered and travel as baggage with the furloughed officer. In the meantime, the chickens provided a steady supply of eggs, very scarce in Germany. Flour and fat (shortening, lard) were also prime ingredients in the packets sent home.96

  Wegener was not rebellious in temperament; he justified his illegal activity as a mandate of his military training to act as a father to his subordinates and to care for them. In this case, given the time-wasting, pointless activity of the Sofia weather station (the hoped-for chance for real research did not materialize), he lived as soldiers came to live everywhere in that war, following those regulations that made sense and willfully ignoring those that did not.97

  He continued to work on science whenever possible; if there was no possibility of actually generating meteorological results from the Sofia station and its satellite stations, he could proceed with “book work.” He generated manuscripts, both reviews and short articles intended for Meteorologische Zeitschrift. He worked on wind speed and direction and, inspired by Porstmann’s book on scientific measurement standards, attempted to sort out and rectify the use of the concept of “friction” in meteorology. He determined that it was being used in at least four distinct ways, and he wrote a short note attempting clarification. He had it in mind to propose a new meteorological element: “Gatterung” in place of Reibung, or friction. The former would be a new unit measuring the severity of turbulence at the border between two air masses, or at the contact surface of two different atmospheric layers. None of this ever saw the light of day. Meteorologische Zeitschrift was fearfully behind in publication, paper was in short supply, and every activity in Germany not directly related to the war was grinding to a halt.98

  In October he received permission from his commanding officer that Else could visit him in November in Sofia. Hilde, as planned, would stay with her grandparents in Hamburg. Arriving in Hamburg with Hilde, Else learned that Richard Wegener had succumbed to his esophageal cancer on 12 October. Alfred obtained a brief compassionate leave to bury his father, and then, together with Else, he traveled to Sofia. November was a good month for them; they traveled widely—she accompanied him on his inspection tours of outlying stations. She pitched in to help with the wrapping of the food parcels to be sent back to Germany. She made the acquaintance of most of the German scientists working at the Bulgarian Meteorological Institute; many of these were colleagues of her father, and they were able to socialize in a way that seemed almost like peacetime.99

  Else returned to Hamburg in December and stayed with her parents. As the financial difficulties increased for their small family, with Alfred’s expenses outrunning his income and allowance, it appeared that they would have to give up their Marburg apartment (convenient to both the train station and the university) and move to cheaper lodgings on the outskirts of town, at war’s end or even sooner. Meanwhile, Else and Hilde could stay in Hamburg. Lack of food was still a consideration, as it was easier to send food parcels directly to Hamburg than try to send them to Hamburg and Marburg both.

  In Sofia, things seem to have been static throughout December and into the New Year. With the success of the revolution in Russia, Lenin and Trotsky had decided to end their war with Germany, and although the Treaty of Brest-Litovsk was not signed until the spring of 1918, there was an armistice on the eastern front. While this decreased the urgency of the meteorological work in Sofia, it produced no letup in the station work itself. Wegener wrote to Köppen in January to say that he was constantly on the move and had no time for work: work here, as always, meant his own scientific work, not his military duties.100

  It appears that there was to be, in early February, a meteorological conference in Brussels bringing together meteorologists from all of the Central powers and perhaps some neutrals such as Bjerknes. Wegener became quite excited about this and wrote to Köppen about a scheme he was developing for a new way to represent wind direction and speed. He wanted to use hash marks of different lengths at boundaries of air masses, thinking of a way to represent the strength and direction of wind within an air mass and thus the likelihood of the development of zones of convergence and divergence.101 This scheme (which was not adopted) he presented
in Brussels in early February 1918. His failure to gain assent notwithstanding, it indicates his continued enthusiasm for dealing with the emergence of turbulent phenomena in the lower atmosphere, and it shows that in spite of his determination to strike this off his list of “67 topics,” he could not help but think about it. It also indicates that the war had succeeded, in no small measure, in turning him from an atmospheric physicist into a “meteorologist.”

  Continental Displacements, 1918

  Just before Christmas, Wegener received a letter from Köppen which included a letter from the Hamburg zoologist Georg Pfeffer (1854–1931). Pfeffer had given a lecture on 12 December 1917 in which he had taken a minimalist position with regard to correlation of species across the Atlantic Ocean. He had read Diener and Andrée, and his criticisms are interesting, because they show the extent to which a specialist in one field may feel entitled to ignore results from another field. Pfeffer said that it was immaterial to him whether or how formerly connected continents came to be separated. He was interested in the distribution of animals and of plants, and neither the geology nor the geophysics of the situation was his responsibility. He would stick to the facts and not worry about hypotheses.

  Apparently, in the question session following the lecture, Köppen had asked Pfeffer whether he was aware of Wegener’s work and of isostasy. Pfeffer was out of time and told Köppen that he would write to him. Pfeffer wrote to Köppen on 14 December and said that he was indeed aware of Wegener and that Wegener’s work on gravity and on Sial and Sima was “theoretically interesting but of no practical significance.”102 This is another way of saying (somewhat more politely than Semper’s “O Holy St. Florian, protect this house and burn another”) that he felt that it was not his responsibility, he didn’t need it, and he didn’t want to talk about it.

  Wegener’s response was interesting and vigorous. “The letter from Pfeffer is typical. He will not listen to anyone. He belongs to that crowd of people who boast about standing on a solid ground of facts and having nothing to do with hypotheses, never realizing that their solid ground of facts has embedded in it a completely false hypothesis!” Wegener nevertheless wanted to hold on to the letter if Köppen no longer needed it, though he added,

  I don’t think it is worth the time and effort to deal with people like Pfeffer. His letter lacks any hint that he has the penetration to get to the bottom of things, and expresses only his joy in being able to find fault with other men’s views. Such people will refuse any reorientation of their ideas. If they had already learned the displacement theory when they were in school, they would defend it for their whole lives with the same lack of understanding, and with the same sort of incorrect information, they now use to defend the sinking of the continents. The best thing is just to wait until they die off.103

  Wegener’s response is revealing in another way: it was clear that even his own father-in-law, with whom he had many times discussed these ideas, fundamentally misunderstood his views on the displacement of Earth’s pole and on the rising and sinking of the continents under load. Here, however, there was an expectation that he was speaking to someone whose mind could be changed. “I have a completely different take on the question of pole wandering than you.” He went on to explain that in opposition to the older view of Kreichgauer (that the entire outer crust of Earth would rotate over Earth’s interior as the result of pressure and motion in the subcrust), he held the more modern view that redistribution of mass in the outer crust, caused by the lateral displacement of continents, must force the relocation of the axis of Earth, as Earth assumes a new ellipsoidal shape in consequence of the motion of the surface masses. The interior of Earth did not have to be in motion; all it had to be was plastic enough that the pole and therefore the equator, 90° away from the former, would move to positions that reflected the distribution of masses at the surface. The technical way of saying this is that “the pole of rotation would move to coincide with the pole of inertia.” This was the view of Schiaparelli and of Lord Kelvin which “Kreichgauer and especially the older geologists know nothing about.”104

  On the question of the rising and sinking of continents and the related question of isostasy, Köppen seems also to have been confused. Hence, Wegener reverted to the question of glacial isostasy: the well-established fact that tide markers in the Baltic Sea were continuing to rise, which exponents of the theory of continental glaciation had explained with regard to isostasy. With the load of thick continental ice sheets removed, the land beneath the ice had risen again. The Sima, the mobile subcrust beneath the continents, played no dynamic role: if the continent were to be pressed down under load, the Sima would flow away laterally; if the load were removed (the melting of the ice), the Sima would flow back underneath, thus lifting the continents. Wegener’s explanation here is matter-of-fact but very simple, slow, and painstaking, almost as if talking to a child.105

  This exchange brought home to Wegener the extent to which his efforts in 1915 to explain geophysics to geologists had been a failure. Even his own father-in-law had not understood what he was talking about. The disconnect between geology, geography, and paleontology on the one hand and geophysics on the other was much greater than he had imagined. Moreover, with his comments about “waiting for people to die” rather than trying to convince them, as well as talking about “the older geologists,” there was a dawning realization that the difference was generational and might not be resolved by empirical evidence or reasoned debate. Younger paleontologists like Andrée and Dacqué had training in geophysics, geodesy, and map projections. They might not agree with all of Wegener’s arguments, but they knew he was correct in the matter of geophysics and its necessity for any general theory of earth sciences. Older geologists had, in the main, neither the training nor the will to understand the arguments, and they simply ignored them.

  Nevertheless, the exchange seems to have galvanized something in Wegener. He had it in mind, since his arrival in Sofia, to establish a wartime colloquium, where the various officers under his command (not all of them scientists) and their Bulgarian counterparts might present the results of their research to one another. He also had access to real scientific institutions—especially the Geographical Institute—with a library and facilities to support such an effort.

  During the first week in January 1918, he inaugurated the colloquium with two lectures on his displacement theory, on two successive days. He addressed his audience at the Geographical Institute, in a room with large wall maps. Reporting this colloquium to Wladimir Köppen in a letter on 9 January 1918, he also responded to new questions from the latter, sent in the interim, concerning the displacement theory. In addition to not understanding isostasy or Wegener’s version of displacement of the poles, Köppen also could not see how the displacement theory could account for the sinking of the land surface. Colleagues in Hamburg had told him that while the Baltic tide markers might be rising, parts of the North Sea were simultaneously subsiding. Köppen then wondered how Alfred could account for a larger subsiding of the land, of the kind that might allow a marine transgression.

  Wegener responded to these new questions with the same calm demeanor that was his habit, even though one suspects he was experiencing considerable frustration. He had, in effect, already explained to his father-in-law that with the removal of the ice cover from Scandinavia, the land must rise as the Sima flowed back underneath the rising continent. This would mean (implicitly—Wegener had not stated it because it was so obvious) that the Sima would flow back in from the oceanic areas surrounding, and that their floors must necessarily then subside. In this letter, however, he took a different approach and explained to Köppen a more general and hypothetical case.

  When a continental mass begins to rift, he wrote, the rift does not immediately open from top to bottom and separate completely. Whatever is pulling the continent apart will at first stretch it, which will produce plastic deformation on the underside of the block, with a certain amount of thinning. On the exposed
Earth’s surface, the opening of the rift would be signaled by a complicated system of faults. Progressively, as the continent was pulled apart, sections of this fault system would drop down and eventually form a large rift valley, with some blocks remaining elevated. When such a rift and fault system reached a shoreline, a marine transgression could proceed even before the rift was complete. Wegener said he believed that this process would explain the appearance of the Aegean Sea (a large map of which he had just been studying at the Geographical Institute), and he interpreted the archipelagoes of the Aegean as the few remaining elevated blocks of a complicated fault system. On the other hand, Wegener wrote, this need not always be the case, and he noted that the split of Africa from South America seems to have proceeded more smoothly and more “of a piece.”106

  This is the sort of back-and-forth interchange which he had had with Hans Cloos in Marburg, where Cloos would offer a geological objection and Wegener would answer with a physically plausible hypothesis, but it was exactly the sort of “picking away” at his theory that came from not understanding the larger geophysical principles involved. Wegener had assumed from the beginning that these general principles, once introduced and understood, would allow his audience to answer their own questions; obviously, this was not the case even for his closest collaborator and patron, his own father-in-law.