Alfred Wegener
Page 7
The freedom to move about in this way was built into the German university system, operating on principles quite unlike those of Britain and North America at the time. In Germany, admission to any university at all was admission to all the universities in the system. Moving to a new university required less trouble and expense than most American students face in acquiring a certified copy of their academic transcript. This immensely rational approach to higher education allowed students to move on to whatever university or universities offered the concentration of disciplines most useful and congenial to them, no matter where they had begun their study. It allowed them not just to major in a subject, but to study that subject with different teachers in different locations, and to see how a subject matter is transformed by the particular approach to the subject a professor chooses, as much as by differences in the contents and methods themselves.
Ruprecht-Karls University, Heidelberg
Taking a summer semester in Heidelberg offered Alfred Wegener a number of advantages. First and foremost, it was far to the west and south of Berlin and therefore away from his home and his parents. In fact, other than Munich and Passau, there were no German universities farther away. Heidelberg lay among hills of forest and vineyard on the south bank of the River Neckar (a rapidly flowing tributary of the Rhine) and about 100 kilometers (62 miles) south of Frankfurt-am-Main. It was an old and picturesque city, most of it in 1900 still running parallel to the river on the Hauptstraße and clustered to the south of one of the larger town squares (the Ludwigsplatz, with its giant equestrian statue of Wilhelm I). It had been extensively rebuilt in the middle 1880s with the addition of a great new library in the Renaissance style to house a collection of more than 500,000 volumes.
Heidelberg was a good choice for another reason: it had acquired considerable fame as a scientific and medical university in the middle of the nineteenth century. It was here in Heidelberg that Robert Bunsen (1811–1899) and Gustav Kirchhoff (1824–1887) made the fundamental advances in spectroscopy which allowed the analysis of the composition of stars by study of their absorption spectra. The university also maintained a new and modern astronomical observatory on the Königstuhl, 335 meters (1,099 feet) above the town. It was much smaller than Berlin, having in 1899 about 150 faculty and 1700 students even at full enrollment in the winter; there were many fewer in the summer. It was therefore easy to find lodgings, and Alfred took a room in a lodging house at No. 5 Heinrich Ingrimmstrasse, very near the university.
Heidelberg in 1900 had its share of famous physicists, astronomers, and mathematicians, most of them with some sort of a tie to Berlin. There was Leo Königsberger (1837–1921), famous for his work in both mathematical analysis and analytical mechanics. In 1899 he had just finished writing a major textbook on differential equations, and his ties with physics gave his lectures on differential and integral calculus a quite different feel from those of Knoblauch at Berlin: it was very much a course of “calculus with applications,” when Wegener took it in the summer of 1900.
In addition to registering for the calculus course offered by Königsberger, Wegener signed up for the course on experimental physics given by Georg Hermann Quincke (1834–1924), a classical, almost premathematical physicist in the tradition of Michael Faraday and the first physicist in Germany to insist that beginning students do practical laboratory experiments in order to learn physics.15 Here finally was a chance for Alfred, almost the first since his and Kurt’s freelance work in the orphanage washroom, to do physics rather than read about it or see it done by others. Quincke built the laboratory exercises around the simplest of materials—pieces of cork, wax, coins. He had done this out of necessity in the early years, not having money for laboratory materials, but he continued it with some pride later in his career.16 Like Faraday, whom he greatly admired, the old physicist delighted in exhibiting fundamentals of physics with everyday materials, in the spirit of Faraday’s Chemical History of a Candle; this sort of deliberate unpretentiousness appealed to Wegener.
The best academic reason for a trip to Heidelberg in 1900 was certainly to study astronomy. Max Wolf (1863–1932), a student of Königsberger, was supervising the completion of a new astronomical observatory on the Königstuhl, for which he had assembled the financing from a combination of royal and private patronage. Both Wolf and his coworker Wilhelm Valentiner (1845–1931) were pioneers in astronomical photography, and like their colleague in Berlin, Marcuse, they used the technique both as an investigative instrument and as a teaching tool, illustrating their lectures with lantern slides. Valentiner had published a photographic atlas of the solar system in 1884, with many of the plates devoted to the Moon. When Alfred signed up for his lectures on general astronomy in the summer of 1900, Valentiner was in the midst of editing a five-volume encyclopedia of astronomy.17 Both Valentiner and Wolf had made extensive studies of near-earth objects such as comets and asteroids, though much of their later fame came from studies of double-star systems and nebulae.
In the summer of 1900, however, Wolf turned out to be teaching not astronomy but meteorology; Alfred signed up for the lectures anyway. It was a mild disappointment perhaps, but he knew something of this subject secondhand from Kurt. Moreover, astronomy and meteorology, now completely separate and found in very different parts of universities, were then parts of the same subject. The etymology of the word “meteorology” groups together all the things “in the air,” including precipitation, tornadoes and waterspouts, and storms, as well as those astronomical objects entering the atmosphere from space for which the word “meteors” is now generally reserved. Added to the historical reasons for grouping them together and having the ensemble taught by astronomers were practical reasons: one had to consider atmospheric conditions in every astronomical observation, and especially carefully in positional astronomy, where one was trying to determine where something was as much as what it was. These atmospheric influences meant that would-be astronomers had to learn how to measure and record temperature and humidity and to correct for their effects. Moreover, whatever one could learn about weather prediction and prognostication was also useful to an astronomer: a falling barometer, high cirrus clouds at noon, and a wind backing from the south to the northwest were strong indications in Heidelberg that an evening planned for astronomical observations might well be spent instead socializing with friends or working in the darkroom.
This was the second time in Wegener’s brief university career that astronomy was presented to him as a subject in which one had to learn first about the earth in order to learn something about the sky. He had begun astronomy in secondary school studying planets and stars. He had read popular works on cosmology, great sweeping stories about the universe as a whole and its life and death. These had provided him scientific nurture where school gave none, as well as a means to transcend the extremely constricting boundaries of his life in Berlin while physics and chemistry, doing what they could, were still trapped in the orphanage washroom. This transcendental power had much to do with his decision to pursue the study of astronomy at the university level. But his first two semesters of university, 1899–1900 and 1900, had shown him an astronomy almost entirely planetary in character, and as much about the earth below as the sky above. Marcuse used the sky mostly to study Earth; Wolf and Valentiner were as yet occupied with Earth’s near neighbors and occasional visitors. All his instructors stressed, in practice if not in theory, that Earth was part of a continuum and a family of similar objects with a common history—the solar system. Moreover, their astronomy was extraordinarily and pragmatically local: not the sky and the universe, infinite and eternal, but this portion of the sky, tonight on this date, here in this place, under these atmospheric conditions, in this moment, recorded on this photographic plate—a universe not seen in the mind, as with the eye of God, but seen through a telescope with the eyes of one local observer.
Being thus brought to earth would have had a greater impact on Wegener had he been a serious young man paying close att
ention to what his instructors were saying, but there is some evidence that he was not. It appears, rather, that Wegener made only two discoveries that summer in Heidelberg: one was sabre fencing, and the other was beer. German universities in 1900 still had the same clientele that all European universities had had for the past 1,000 years: boys turning into men. At Heidelberg as elsewhere in Germany, they gathered in bands distinguished by the colors they wore: Farbenbunden (color bands). These organizations, semimilitary in character, were an important part of university life—an exclusively male preserve. Close counterparts of North American fraternities, they were then as now fundamentally contentless vehicles for male bonding expressed in initiation rituals, sports, organized nonlethal aggression and threat displays, singing, and the consumption of beer.18
The universities in Germany, as in the United States, France, Britain, Austria, and the other great industrial states, were also the principal training grounds for the officer corps of the armies and navies, as much as for the learned professions. Given the scale of military preparedness and the capacity for mobilization necessary to win a war at the end of the nineteenth century, European powers could no longer depend exclusively on an aristocratic and hereditary officer caste. The latter might make up the corps of career, active-duty officers for the standing army, but there was also a need for a corps of reserve and replacement officers. The empire therefore encouraged the adoption of military rituals and mores by doctors, lawyers, magistrates, pastors, professors, and the upper strata of the commercial bourgeoisie—bankers, merchants, and the indispensable legion of civil servants who kept the empire moving forward in orderly fashion. These youthful deposits of fraternity, patriotism, and mutual trust were banked against the inevitable day when these men’s deaths would become more valuable to the state than their lives.
So Alfred Wegener joined a Farbenbund—which color no one any longer remembers. He went to the fencing hall with his color-brothers, put on the heavily padded tunic and gauntlets and the protective headgear, and learned to cut and slap with the heavy and dull-bladed cavalry sabres used in fencing competition. There was no flexible foil, no thrusting épée, just a broad-bladed sabre, meant for slashing and cutting, making a thunderous clash and clang as the pairs of combatants up and down the hall parried and cut to the encouraging shouts of the assembled brethren. In the evenings, after supper and study or bypassing study altogether (it was summer, after all, and examinations were years away), they repaired to the beer halls for singing and, of course, beer and tobacco. They drank their beer in half-liter and full-liter quantities, served off rolling carts running the aisles between the long tables and benches, along with potato salad, sausages, onions and radishes, and bread. They smoked black shag tobacco in long pipes with ceramic bowls, or smoked cigars, more often cheroots than the fat stogies that were thought to be a smoke for old men. The room grew hot, and they sweated their collars and grew red in the face. The band in the stand in the middle of the hall, on a raised platform like a prize ring with no ropes, played thunderous choruses of polka and martial music and marching songs, and the Farbenträger bellowed the lyrics and pounded the rhythm on the table with their fists or their beer steins.
On one such night, between Tuesday and Wednesday, 3 July 1900, at about three in the morning, Constable Eiermann of the Heidelberg Police was summoned to the Marktplatz to answer a noise complaint. He intercepted the perpetrator on the Hauptstraße and issued the following summons: “The aforesaid Alfred Wegener, Heinr. Ingrimmstrasse No. 5 is accused of disorderly conduct and disturbing the peace, in that he, wrapped in a white sheet, was proceeding down the Hauptstraße toward to Marktplatz and provoking thereby, through his too-loud shouting, an unseemly disturbance. On the basis of paragraph 360 of the Municipal Code, a fine of 5 Marks will be assessed against him. He must also pay costs. Failure to appear and pay the fine carries a jail sentence of two days.”19 Alfred appeared at the police station on Friday and paid his five marks and court costs of 20 pfennigs, and he was issued a copy of his summons and a receipt. He kept the document for the rest of his life as a sort of declaration of independence. The discipline of the parental home was exceedingly strict, and he had finally been able to shrug it off, even if only temporarily.20
Berlin, 1900–1901
Alfred traveled at the end of the semester from Heidelberg to die Hütte, for some vacation time with Kurt, Tony, and his parents. The latter were certainly not informed of the matter of the bed sheet and the predawn meeting with Constable Eiermann, though they no doubt got news of the fencing hall and such other matters as were suitable for parental consumption. It was time to hike and talk with Kurt and plan for the second year at Berlin. Kurt was progressing well in meteorology at the Technische Hochschule in Charlottenburg; perhaps because of Kurt’s account of these experiences, as well as Alfred’s own introduction to the subject from Max Wolf in Heidelberg, Alfred thought about adding meteorology to his program. What he heard from Kurt was rather different from what he had studied at Heidelberg: it was much more comprehensive and three-dimensional, and much more like doing physics than astronomy. But there was still the preparation in physics and the mathematics needed to do it, so these had to come first.
The schedule Alfred planned for the winter semester of 1900–1901 was more rigorous than that of his first year. The mathematics course was differential equations with Lazarus Fuchs (1833–1902). Fuchs’s approach to the subject was an excellent means of continuing the work on calculus Alfred had done in the previous semester. Differential equations are the essential language for much of mathematical physics. In solving a physical problem—like the rate of change of temperature of some object as it is heated in the open air—the heart of the solution is the writing of the differential equation that expresses the relationship of the various physical quantities that enter into the problem. Of course, one needs measurements of physical quantities to put into the equation as terms, if there is to be a specific rather than a general or purely mathematical solution to the problem. Indeed, the terms of such differential equations—temperature, pressure, density, cross-sectional area—presuppose physical processes and measurements. The study of the construction of differential equations is the gateway to doing physics, since most problems in physics are answered with an equation—a concise expression of fundamental relations of quantities in mathematical terms.
Just as challenging as Fuchs’s course in differential equations was that of Max Planck (1858–1947) in general (theoretical) mechanics. This subject, since the onset of the quantum-mechanical worldview, is now called classical mechanics or analytical mechanics. It is a unified approach to physics through concepts of motion and is still offered in modern university physics curricula. Then as now, a course in differential equations is usually a prerequisite or corequisite, and the organization and treatment of the subject are historical. Students began with the development of a physics of force and Newton’s laws of motion. This treatment was then extended to the ideas of work, energy, and the “conservation laws”—particularly the conservation of momentum and the conservation of energy. Such a course usually ended with a physics of energy based on the formulations of Joseph Louis Lagrange (1736–1813) and William Rowan Hamilton (1805–1865). Along the way students were introduced to the mathematical treatment of classical problems: central-force motions and the orbits of planetary bodies, oscillations and harmonic motions (pendulums, springs, floating objects bobbing up and down), and the motion of rigid bodies, where the objects treated are no longer considered as point masses with a location only, but have a shape and an orientation (such as a center of mass). It was fortunate for Alfred that he had moved as far along in mathematics as he had: his friend Lietzmann had attempted this course without differential equations and had not understood much.21
The autumn of 1900 also brought the first of Alfred’s many courses with the astronomer Julius Bauschinger (1860–1934), at forty already one of the world’s leading figures in the very specialized field of det
ermining the orbital paths of heavenly bodies. Bauschinger had come to Berlin from Munich as professor of astronomy in 1896, after the death of Friedrich Tietjen (1834–1895). Bauschinger was interested in orbits and only in orbits, and he fitted in well at Berlin, where, with the exception of Prof. Scheiner, everyone worked on the measurement and calculation of locations, orbits, and distances; the calculation of planetary tables (ephemerides); and the refinement of methods for correcting observational errors.
Berlin astronomy in 1900 was classical celestial mechanics with a vengeance: very exact, very technical, very powerful, and very narrow. The astronomers at Berlin, led by Wilhelm Förster (1832–1921), who had started his teaching career there in 1858 and would continue to lecture until 1920, were strongly oriented to the history of astronomy, and therefore some aspect of this topic was offered almost every semester. The faculty was small and the viewpoint severely limited. Between 1899 and 1904, bracketing Wegener’s time as a student in the department, there were really only three active professors, Förster, Bauschinger, and Scheiner, and two docents, Adolf Marcuse and Hans Battermann (1860–1922). Battermann never taught more than one course per semester, and it was almost always a technical course on observing the Sun. Scheiner taught astrophysics and observation of stars, and Marcuse taught only introductory astronomy and technical courses on position finding. This left Förster and Bauschinger to do all the rest of the teaching, and thus the courses rotated through their sequence very slowly.