Later Years in Marburg

All the research activity described in the foregoing sections had a significant and very positive effect on Kolbe's career. From an average of twelve students per semester in Kolbe's practica of 1859-1860, the number increased to an average of twenty-two during the years 1860-1865. Average attendance at his lectures increased in the same period from thirteen to nineteen, and chemistry majors increased from essentially none to about nine per semester. At the same time, the average enrollment at Marburg increased only about two percent.^[88]

These changes came none too soon for Kolbe. On the last day of 1860, he wrote Vieweg

I may boldly assert that over the last two years no German university laboratory, even including Göttingen, has produced so many truly good chemical papers as has mine; at the same time Göttingen, Heidelberg, and even Giessen (where for a decade almost nothing has been accomplished) are overflowing with students.

Given the political situation and the reputation of the despised Kurhessian prime minister Daniel Hassenpflug, no one wanted to come to Marburg, Kolbe thought. Foreign students, the real mark of success, were especially notable in their absence; only in rare semesters were there any at all.^[89]

If Kolbe's great break as far as research is concerned occurred in 1858-1860, a similar break as far as student numbers are concerned came in summer semester 1862. Classroom enrollment and total numbers of Praktikanten were still about the same, but now he had five real chemistry majors as well as a number of advanced workers in the lab, including no fewer than six who already had Ph. Ds. Two of these six were his long-term prize students, his assistant Lautemann and his former assistant Schmitt. A third was a certain H. Scheuch, who pub-

lished one article from the Marburg lab but is otherwise obscure. A fourth was Bunsen's former student Carl Graebe (1841-1927), who stayed just that one semester and never offcially matriculated; he returned to Heidelberg that fall as assistant to Bunsen. He subsequently spent four extraordinarily productive years as assistant to Baeyer; his teaching career included periods at Königsberg and Geneva, and he was also involved with the early history of the Hoechst dye firm.^[90]

The fifth of Kolbe's Ph.D. workers that summer was Jacob Volhard (1834-1910), a former student of Will and Kopp at Giessen, who had served as assistant successively to Bunsen, Liebig, and Hofmann before his arrival in Marburg. Volhard's stints in Munich and London were relatively long ones (four and two years, respectively). He has been called Hofmann's oldest German student, but it appears that it was more Liebig's recommendation than Hofmann's that led him to Marburg. After working with Kolbe for three semesters, he returned to Munich, where he occupied the lower academic ranks for the next sixteen years. He accepted calls to Erlangen in 1879 and Halle in 1882. In his single publication from Kolbe's lab, Volhard insisted on using the reformed weights for carbon and oxygen—the first such publication from one of Kolbe's students. No doubt this was due to Hofmann's influence, from whom he had just come.^[91]

The last of the six was the Scots chemist Alexander Crum Brown (1838-1922), who had studied with the English Liebigians William Gregory and Lyon Playfair at Edinburgh and London, but who had also been strongly (if indirectly) influenced by Frankland, Kekulé, and Wurtz. After leaving Kolbe, he spent a year with Bunsen before returning to Edinburgh, where he succeeded in making a fine academic career.^[92] In addition to these advanced workers, we also know that Edmund Drechsel (1843-1897) was in Kolbe's lab in 1862 as well. Drechsel later worked with Volhard in Munich and with Kolbe and Carl Ludwig in Leipzig. He became a well-regarded physiological chemist and physiologist, teaching for many years at Leipzig and at Berne.^[93]

It was just at this time that Kolbe began to attract a steady stream of Russian chemists. The first to come, in that busy summer of 1862, was Konstantin Zaitsev (or in German transliteration, Saytzeff); the following semester he was joined by his brother Aleksandr Mikhailovich Zaitsev (1841-1910), who subsequently became far more famous. After two semesters, Konstantin left the lab, but Aleksandr remained there until Kolbe left for Leipzig. In the spring of 1863 three new Russians arrived, and in the following year came three more; in Kolbe's last semester in Marburg, Nikolai Aleksandrovich Menshutkin (1842-1907) studied with him. Butlerov, then at Kazan where many of these

men studied, must have advised several of them to travel to Marburg for foreign education.^[94]

We can follow the rise in Kolbe's fortunes by following his increasingly proud reports to Vieweg and to Frankland. In winter semester 1862/63, there were eighteen Praktikanten, and in the following semester twenty. In summer semester 1864 no fewer than thirteen of the eighteen Praktikanten came from outside Kurhessen. In the fall of 1864 the overall number jumped to twenty-nine, which, counting a few unmatriculated advanced workers, exceeded the capacity of the lab. Moreover, ever larger numbers of foreign Germans—Prussians, Saxons, Bavarians, and so on—were enrolling. Even non-German foreigners such as the nine Russians named, three Englishmen, two Scotsman, two Swiss, and two Americans enrolled during Kolbe's last two Marburg years. One of the Americans was Charles W. Eliot (1834-1926), who attended Kolbe's practicum in winter semester 1864/ 65; four years after that he became the president of Harvard University.^[95] One of the Englishmen was E. T. Chapman, who later published some excellent research in organic chemistry before his untimely death in 1872. Most of the foreigners at the entire university, Kolbe bragged in one letter, were his students, and the University's matriculation registry bears out the boast.^[96]

By the early 1860s Kolbe had earned a remarkable international reputation. A knowledgeable anonymous reviewer writing in the Westminster Review in 1866 thought that "the Marburg laboratory has played a very considerable part in the chemical history of the last seven years," and he referred to Kolbe as "one of the few chemists who have succeeded in forming a school." Kolbe's pupils—he named Lautemann, Griess, Guthrie, and Ulrich—he thought were "distinguished for a certain kind of originality, and for great practical skill." Moreover, the writer regarded Kolbe as next to Liebig "the most successful chemical teacher in Germany."^[97]

No detailed descriptions or university records of Kolbe's laboratory practicum have survived, but the general course was given in chapter 5. All surviving testimony indicates that Kolbe's teaching was conscientious, effective, and deeply appreciated by his students. We have cited comments regarding the Marburg years from Guthrie, Graebe, and Volhard, also in chapter 5. Kolbe hated the lab, referring to it as a "junk box" (Rumpelkasten ). He suffered regularly from breathing the fumes—hydrogen cyanide was a common reagent—and considered the lack of ventilation to be positively dangerous, with good reason.^[98]

In 1862 Kolbe was still working in essentially the same laboratory that he had inherited from Bunsen, which the latter had had constructed over twenty years earlier.^[99] The lecture room was renovated

in the summer of 1856, but the modest extent of the alterations is indicated by the fact that the work cost only 145 thalers. Moreover, the laboratory budget was wholly inadequate, a fact that Kolbe brought to the attention of the administration by ignoring it as regularly as possible. This did little to win him friends among his superiors and among colleagues in oversight committees. In the fall of 1860 the budget was increased from 700 to 800 thalers, but Kolbe was made personally responsible for any overages—a ruling that enraged him for weeks, so intensely that he could not work. Moreover, the budget was only designed to pay for equipment, instruments, and lecture experiments, not the consumption of chemicals by Praktikanten, who had to foot that bill themselves. He complained that his salary was barely half as much as would suffice to keep a family in proper style, particularly since his income from student fees was exceptionally low until around 1862.

But Kolbe's sudden success in research dramatically increased his local power and leverage; Liebig's public approval after 1860 undoubtedly also helped. In July 1861 Kolbe received his first raise in Marburg, from 600 to 700 thalers; eighteen months later it was raised again to 800. In early 1865 his salary increased once more, to 1000 thalers (but to add a note of perspective, Bunsen was earning 1200 thalers when he left in 1851). Finally, in May 1863 his often-reiterated proposal to renovate and expand his lab was finally accepted, and the work began immediately. Considering that no new spaces had to be constructed, the total cost of this renovation was relatively large, about 2000 thalers. The extent to which Kolbe's stock had risen can be seen by the fact that during that same summer, his laboratory budget was raised to 1000 thalers and a salary line for a second assistant was authorized. By the end of his Marburg years, Kolbe was making more than four times what he had been earning earlier from student fees, and his prestige was such that he could simply ignore all budgetary restrictions.

The laboratory space was completed astonishingly quickly, by the beginning of the next term (11 November 1863). The new lab was expanded to fill the entire west wing of the Deutsches Haus, including the space previously devoted to the lecture room, and could now be divided into sections for beginners, advanced workers, and large-scale general operations. The servant's residence in a small adjoining space was converted to a private lab for the institute director and was separated from the main lab by a glass partition. Smaller spaces were created to serve as a stockroom, a eudiometry room, a wardrobe, and a roofed open-air area for working with hazardous fumes. The east wing of the old building was converted to a large, light and airy lecture room, displacing the collections of the zoological institute. On the

second floor of the east wing, spaces were prepared for a balance and equipment room, a general storeroom, and a darkroom for photographic and spectrographic work.

A significant expense must have been incurred by Kolbe's insistence that every two work spaces be provided with water taps (connected to a reservoir filled from the nearby Lahn River) and every station equipped with gas for Bunsen burners. This was a comparative novelty at that time and was made possible by the simultaneous laying of gaslight installation for the city of Marburg. The lab was also equipped with a hundred gas illumination burners, so for the first time, work could continue after sunset. The net effect of this renovation was to more than double the total actual laboratory space—all three sections together measured about eighty by twenty-five feet—and to increase capacity by half, from about twenty to around thirty Praktikanten. The only thing that Kolbe still desired was an on-site residence for himself.^[100]

Kolbe was immoderately proud of his new lab. It was not just a good, it was an "elegantly outfitted laboratory," somewhat smaller but even better equipped than Bunsen's in Heidelberg and very similar to that in Göttingen. He reported to Vieweg that the gas burners, both at the bench and overhead, allowed him and his students to work about twice as fast as was previously possible. To his administration, he predicted a "new era" in the history of the chemical institute.^[101]

This new era, at least under Kolbe's aegis, was of short duration. Less than two years later he exchanged Marburg for Leipzig.