The photo from 1913 (Figure 1) shows 18 final year students from the 4.5 year Fabrikingeniør (i.e. “chemical engineering”) at 'Polyteknisk Læreanstalt' (in the following abbreviated to PL), at that time, a College of Advanced Technology modelled after the German Verfarhen Institut.
The photo is taken outside of the Dräger factories in Lübeck, Germany on a summer excursion. With the students is Professor of Technical Chemistry, cand.polyt Niels Georg Steenberg (1839-1915) who in September 1913 retired from PL. The elderly gentleman is found in the front row along with employees from Dräger. To the right of him, in the back row, stands his successor Peter E. Raaschou (1883-1971) with a bowler hat and a sardonic smile, characteristic of photos of him. Raaschou had recently in June of 1913 been appointed Professor from September 1st 1913 after a tough competition for the position.
Drägerwerk was founded in 1889 by Dräger and Gerling in order to, among other things, establish a CO2 plant for beer production. Today, the
company has grown to a global joint-stock company (AG),that still produces the “Dräger tubes”, sold by the company from the early days for colorimetric analysis of gasses.
Excursions “abroad” to close by countries were carried out as early as the 1870’s for the last year students. Often to chalk and cement factories around the Swedish city Helsingborg, but also to “chemical companies nearby Copenhagen”. The tradition lived on until the 1980’s when the destination of the excursions was often distant countries. Memories from the excursions could bond the class close together for life, and it is a pity (but also inevitable) that the tradition petered out as the class in modern curricula was divided into more and more specialized areas – and holidays with the family to exotic countries became common.
Women in chemical engineering
It is interesting that five out of 18 students in the photograph are women. The yearly report from PL, 1913/14 [2, p. 8] lists that at the winter exam 1913/14, 24 Fabrikingeniør-students were approved for examination, of which 23 passed. Seven of these were women. Three were awarded the degree laud, (Latin for “praiseworthy”, four were awarded the degree “not un-praiseworthy”, while the degrees for the 16 men were divided into eight 1st degrees, seven 2nd degrees and one 3rd degree = “should not be despised”. Neither the gender distribution, nor the attained marks for the chemistry students in 1914 is much different from that of 2016 graduates, Of the graduating students in 1914 there are no women among the 23 mechanical engineers, one among the 54 graduating civil engineers and none among the 14 electrical engineers.
Professor N.G. Steenberg
What do we really know about the key figure in the photo [figure 1], Professor N.G. Steenberg? From the PL report, 1 August 1894 to 31 July 1895 [3, p. 890] we learn that “Because of Professor A. Thomsen’s passing away in September 1894, cand.polyt, Niels G. Steenberg, was put in charge of most of the teaching in Technical Chemistry for the autumn semester and of the December-January examinations in 1894/5, as well as a series of lectures on inorganic technical chemistry in the spring semester”. “After the exams of January 1895, the question of the long-term occupation of the teaching position in technical chemistry was raised in the teaching council. Several applications had surfaced, “but as the candidate Steenberg wished to be taken into consideration, and because of his display of satisfactory abilities to lead the process of lecturing and examinations, the teaching council found him the most qualified of the applicants.” N.G. Steenberg was appointed for the position and “on February 25 1895 announced as Professor of Technical Chemistry as of March 1st 1895”
Niels Steenberg graduated as fabrikingeniør in 1861. He first worked as a teacher at a private school and was afterwards employed at the Technical School of Copenhagen from 1862 to 1864. Subsequently, he worked for almost 30 years at the company, Jacob Holm and Sons, located in the outskirts of Sundbyvester which we today know as Amagerbrogade, close to Amagercentret. His charge rapidly became that of factory manager or “Technical Director” as we would call it. Jacob Holm (1770-1845) was the largest ship-owner and ship builder of his time, but he was also involved in factory business: from 1808 a Dutch mill, from 1809 a glue factory and from 1812 a rope-walk on the premises of the plot in Sundby. The chemistry companies in Denmark existed until the First World War and today, polymer fibers are produced with headquarters in Switzerland. In an homage to Steenberg issued by the weekly newspaper Ingeniøren in 1910, we learn that Steenberg with great technical insight expanded and modernized the company's soft soap production, and he managed to relocate the smelly cooking of glue further away from the closely settled part of Amager.
Certainly, the hiring procedure described above looks unsatisfactory, based as it is on a single semester of teaching and without reference to a single publication from the chosen applicant. Unfortunately, this impression seems to be confirmed by Steenberg’s 20 years as a professor at PL. I have not been able to find a single testimony of Steenberg’s participation in written academic research, or even of popular works on technical chemistry. But the students loved him as witnessed in  and described in my essay.
The Brothers Thomsen
It is worth mentioning that Steenberg wrote a comprehensive and very positive biography about his predecessor, Professor Carl August Thomsen (1834-1894), in Dansk Biografisk Lexikon . Just as his successor, P.E. Raaschou,, wrote a beautiful obituary for Steenberg in Ingeniøren . C.A. Thomsen was the eight year younger brother of Julius Thomsen (1826-1909), the great scientist within inorganic chemistry and thermochemistry and President of PL from 1883 to 1902 . Carl August graduated from PL as cand.polyt in 1858 (Applied Natural Sciences, Chemistry). Hereafter, he was - in a modern terms - Postdoc for a year at laboratories in London and Paris, after which he worked as an assistant at KVL, the Royal Veterinary Institute, from 1863 to 1871. From 1871 Carl August was employed as docent in Technical Chemistry at PL.
The life stories of the two brothers were closely intertwined.
Through many years, Carl August and Julius Thomsen worked together in academia, and it is entirely possible that the younger brother had a better grasp of technical chemistry than the famous Julius. He wrote about many topics in a reader-friendly manner, and his printed copy of “Forelæsninger over teknisk Kemi” (“Lectures on Technical Chemistry”) from 1883 was for many years used as a text book.
Together they wrote about the use of kryolite (Na3AIF6) which Julius had described and in 1859 patented – unfortunately to be used in the production of soda (NaHCO3). A significant part of the world’s largest kryolite mine at Ivigtut in Greenland, was used for soda production using a process which - after a few years - was made obsolete by the Solvay process. The most important use for kryolite is as a liquefier in aluminum production. The oxide AI2O3 is melted into a eutectic mixture with kryolite and is subsequently reduced to AI through electrolysis by processes discovered in the 1880’s. Around 1970 the mine was exhausted, but at its peak in 1943 when allied (war)airplane production was on its highest, the mine’s significance for the warfare of the allied forces was paramount.
In ‘Tidsskrift for Physik og Chemi’ (“Journal for Physics and Chemistry”) [Figure 2] founded by the brothers in 1862, the knowledge of Julius Thomsen’s epochal work within thermochemistry as well as Carl August’s examinations of beer, oil and gas was disseminated. At the same time, the journal followed the development of new, rapidly growing industries such as sulphuric acid and soda production. In most of the 30 years of the journal’s life-span, Carl August was the sole editor with support from friends from abroad.
Therefore, it was with good reason that the awarded Carl August with the newly created chair as Professor of Technical Chemistry in 1984. Sadly for the college as well as for its President, Julius Thomsen, the hard-working and popular Carl August Thomsen passed away from cancer after olny four month in the position.
Carl August Thomsen could very well be seen to founder of education and research within what is today viewed as the multifaceted discipline Technical Chemistry at DTU.
Raaschou and the competition for the chair
In the 1912-13 yearbook for the University of Copenhagen (+ KVL and PL) , one finds a description of the process for hiring Peter E. Raaschou as the successor of Niels Steenberg for chair in Technical Chemistry. The procedure for the professor competition, the appointing of the assessment committee and the course of the competition is carefully outlined. It is clear that the 1913 hiring procedure was more thorough than it was in 1894 when Professor Steenberg was appointed. The eight applicants are mentioned by name and occupation. It is decided that the committee, in addition to six members from the college’s corps of professors, should consist of members from Danish industry. Of the six persons appointed by PL five are “chemists”, namely the professors Einar Biilman (organic chemistry), J.N. Brønsted (physical chemistry), Julius Petersen (inorganic chemistry) and Orla Jensen (professor in “biotechnical chemistry”, at least from 1915 according to the 1915-16 annual report where he is mentioned for the first time), as well as, a bit unusual perhaps, the soon-to-be-retired, Niels Steenberg. Every applicant was asked to give a two-hour lecture on a technical chemistry-related topic of his own choice, as well as a two one-hour lectures about two technical chemistry-related topics defined by the assessment committee. For every lecture a manuscript had to be handed in for review.
The two-hour self-chosen lecture was delivered on the 23rd to 26th of April 1913. The topics were to be handed in “in a sealed envelope to the committee on April 5 at 10.30 where the order of the lectures would be decided by a draw". Raaschou’s topic was “The significance and application of catalysis in the chemical industry illustrated by some examples” [Figure 3] and it was later published as a special edition in Ingeniøren, vol. 88, 1913.
With regards to innovation and relevance for the development of Technical Chemistry, Raaschou’s lecture stands far above the others’, for example "Moderne bestræbelser i retning af rationel udnyttelse af store tørveforkomster" (“Modern attempts towards a rational utilization of large deposits of peat”). Perhaps in acknowledgement of the retiring professor who helped the peat industry a lot?
The topics for the two one-hour lectures were announced on April 28th and May 5th respectively and were to be delivered on April 30th and May 7th. To topics were “Fabrication of cyan connections” and “A characterization of the methods and apparatus applied for filtration in the larger chemical industry”.
From the results of the set and free-topic lectures, the committee concluded that two of the applicants “have shown to possess such abilities and skills that could qualify them for a faculty position at PL”, but that the committee “unanimously support the Teachers’ Council that the vacant position as Professor of Technical Chemistry be filled by cand.polyt P.E. Raaschou who at the competition has demonstrated that he is in possession of excellent abilities in the field, and a remarkable disposition to organize the education for the students”.
One may wonder how these lectures could make the foundations for the last part of the above statement, and with the current criteria for hiring professors in mind one may wonder why not a single publication from the applicants was considered. Perhaps the explanation can be found in the recommendation of the time from the management of PL, where statements by the President (Professor H. I. Hannover) at the Annual Commemoration Days during the years 1913-1920 expresses his concerns that "working primarily as a scientist rather than as a teacher ... could lead down a path inside the labyrinth of science that ends blindly" (Beretning 1/8 1917 – 31/7 1918, p.30). Furthermore, a certain meekness is expressed towards the great, new technical "universities" in Trondheim (NTH) and Stockholm (KTH), and particularly towards the tremendous development in (technical) sciences in the warring countries during 1914-1918.
Moreover, the festive speeches during these years provide superb reading if one tries to imagine the challenges for the management as well as the students of the PL at a time where SU (State education grants) did not exist and where having a job beside one's studies was essential for many students. It could even "make them better engineers". Indeed, there is room for good news: For instance the establishment 1n 1916 of the Technical Doctorate, first rewarded in 1918 to Professor (and electrophysiologist) Julius Hartmann, the result of the great construction work at PL since 1908, and the curious message that the whole operation of PL during the past 30 years "has been financed by a fee on the kryolit mining in Ivigtut created by the genious Professor Julius Thomsen".
The excellent result of P.E. Raaschou in the competition for professorship in 1913 was partly founded his good, yet not brilliant, result of 1st degree in the final exam as cand-polyt in 1895. His co-student (and later colleague for many years at PL as teacher in electro chemistry) Dr. Phil. Sven Palitzsch passed the exam with distinction. However, Raaschou further educated himself, first within fermentation physiology in Alfred Jørgensen's Laboratory at Frydendalsvej in Copenhagen, then at the prestigious Heriot Watt University in Edinburgh (1905-1907), then as assistant at the Fresenius analytical chemical laboratory in Wiesbaden (1907 – 1910), and finally in 1910-1912 as COO of Weimarfarbe GMBH. From these stays abroad, two of the few scientific publications from the hand of Raaschou derive, one about a microchemical methodology for determination of Hg, and one about durability of color compounds.
A zeitgeist of basic science around World War 1
The competition lecture of Raaschou fully matched the level of this discipline in 1913. In this year, Michaelis and Menten published the first mechanism for (enzymatic) catalysis, and the methodology of Haber and Bosch for producing NH3 by high pressure and relatively low temperature was developed in Germany in the years 1905-1913. Langmuir´s mechanism for inorganic catalysis on metal surfaces was five years into the future (1918). Jens Anton Christiansen (1888-1969), cand polyt in 1911, teacher and researcher at KU (University of Copenhagen) in 1915, and Professor in chemistry at KU from 1931, worked on the mechanism for homogeneous catalysis in the gas-phase. If Raaschou in collaboration with JA Christiansen had investigated the topic, the credit for discovering the "transition state" mechanism for chain reactions (and the following Nobel Prize) may have been bestowed upon Denmark. If one studies the photography  of the delegates of the first 'Nordiske Kemikermøde' (1st Nordic Chemists Meeting) in Copenhagen in 1920, one finds that, in addition to Raaschou and J.A Christiansen, a series of the finest chemists of the time are present, such as Johannes Brønsted, Niels Bjerrum, Orla Jensen, Kaj Linderstrøm-Lang and many other Danish scientists. It is a mote question what these scientists in collaboration could have done for Danish science and industrial development at a time of scientific upheaval within Chemistry and Biology?
A very quiet period in Danish chemical engineering
Unfortunately, the good beginning leading to the appointment of P E Raaschou as professor in 1913 did not continue. In the annual reports of PL from 1915 to 1926 the scientific production of the faculty is listed. One finds no references to publications from Raaschou besides 'Forelæsninger over Teknisk Varmelære (for ikke fabrikingeniører)' in 1918/20, along with a few small contributions in 1921-1925.
In 1949, when Raaschou's encyclical book on Technical Chemistry (957 pages) ”Forelæsninger over Almen Teknisk Kemi” was finally published and printed, time had long since run out for these types of encyclopedic text books. Hougen and Watson's book series in three volumes (1943, 1943 and 1947) encompassed the Anglo-Saxon approach to the subject. In 3 volumes “Materials and energy balances”, “Thermodynamics”, and “Kinetics and catalysis” laid the foundation for teaching of Chemical Engineering all over the World.
Vagn Ahrend Larsen's detailed description in Dansk Kemi  of the legacy of PE Raaschou, depicts a diligent teacher who was loved by his students and who provided Danish industry with much assistance (and who was also elected as a member of numerous boards). However, this does not change the fact that 'Afdelingen for almén teknisk Kemi' during the last years of Raaschou's 40 year "regime" - an adequate term for a structure where one professor was trendsetting - withered away.
When the description of catalytic processes in the 1949 text book does not differ from the printed version of the lecture in 1913 something is wrong. Here it doesn't help that students like the course, as they will not discover the changed scientific background before they try their strengths against the technically and scientifically educated Americans and Englishmen who have received a more appropriate education.
The construction of a pilot plant showed the way
It was a great benefit to Denmark that Raashcou during the troubled years of the Second World War, opened his pilot plant, largely expanded after 1932, to the research of Haldor Topsøe (1913-2013) and Anders Nielsen. Hereby the PL contributed significantly to develop their later world-famous NH3 catalysts and demonstrate that the Vanadium catalyst for SO2 oxidation is distributed in molted form on the carrier. It should not either be forgotten that the large machinery built by Danish engineers made a company such as F.L Schmidt world famous during most of the 20th century for building and running cement factories. The technically sound education at PL and the high standard of its candidates made this possible, despite weaknesses in the up-to date scientific content of Technical Chemistry at PL.
Those who managed the chemical engineering education at PL deserve our gratitude for their contributions to the development of the chemical industry. Still, it is a blessing that the Department of Chemical and Biochemical Engineering is now "running" its business on a solid foundation of basic sciences. The success of the large and still expanding pilot plant to attract students from all over the World and contribute results to Danish industry witnesses that the Department of Chemical and Biochemical Engineering offers a broader education then most competitors and is able to couple front line Science with research that takes the processes to large, industrial size.