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THE BARON JUSTUS VON Ueblg MEMOR1AL Lecfure 1997 Justus Von Liebig - the Gatekeeper of Chemistry

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THE BARON JUSTUS VON Ueblg MEMOR1AL Lecfure 1997 Justus Von Liebig - the Gatekeeper of Chemistry THE BARON JUSTUS VON UEBlG MEMOR1AL LECfURE 1997 Justus von Liebig - the gatekeeper of chemistry Professor W.H. Brock, BSc, MSc, PhD Department of History, University of Leicester, Leicester, UK While travellin g around Au stralia in 1989 I was repea tedly ex plosive sil ver fulminate, a salt of fulminic ac id. Cyani c acid made aware of th e presence of Justu s vo n Liebig ( 1803-73), was then being analysed in Berzelius's Stockholm laboratory Near Ali ce Sprin gs I came across Mt Li ebig. in the Port by the YOllllg Friedrich Wohler ( 1800-1882), who showed that Curti s di stri ct of New South Wal es I learned of a Li ebig its compos ition was identical wi th Liebi g's fu lminic aci d. After County, as we ll as a Li ebi g Street in Warrnambool on the the two young chemi sts had met at Frankf11l1 in 1826 and gone Great Ocean Road 10 the south west of Melbourne. through their respecti ve preparations and ana lyses And at Irra w<lllg in New SO llth Wal es a tombstone together, each agi'ecd that their ori gi nal f1ndings had commemorating the li fe and achi evements of been justifi ed. James King ( 1796-1857), a Scots freeholder Not on ly did th eir liule di sagreement lend who emigrated in the 18205 and who to the greatest fri end ship and partnership in pioneered glass-making and wine growi ng the hi story of chemi stry (over a tholl sa nd in the stat e. mentioned his friend ship letters exchanged over th eir li fetimes have wit h Li ebig . Clearly. Li ebi g was a survi ved) , but it was one of the prin cipal chem ist with a world reputation, and as factors wh ich led Bcrze li us 10 ann oun ce Mark Finlay has emphasised, he was th e doctrine of isomeri sm in 183 1- (hat one of the more signifi cant ninctecnth ­ two (or more) substances mi ght have the cenlUry scienti sts in shap in g an sam e elemcnt ary compos ition , yet international vi sion of science and it s different properti es, because th ei r atom s enterpri ses. I . were differently arranged. By the time of Berzelius's annoullce­ A Life in Chemistry mem, of course, Wohler had made an even more sensati onal di scovery, In 1828, as he Liebig's father was a pigmelll and drug told Li ebig excited ly, he had found that th e dea fcr in Darmstadt, where Li ebig was urea ex tracted {'i'olll a dog's urine had exactly born on 12 May 1803. After edncation at the same composition as ammonium cyanate. the Darmstadt Gy mnasium, Li ebi g was for a Between them, and in the space or 11 decade. short time apprenti ced to an apothccary in Li ebi g and Wohl er had revealed the so urce of the Heppenheim, but financial diffi culti es forced hi s ri chness, fasc in ati on and diffi culty of organic return to help in hi s father's shop. In 1820 he bcgan chemi stry, namely that the simpl e elements of carbon, the serious study of chemi stry with Karl Ka stn er oxygen, hydrogen and nitroge n are capable of combining (1783- 1857) at the Pru ss ian University of Bonn , following rogether in myriads of differe nt ways to produce myriads of Ka stner to the Uni versity of Erlan ge n in Bavaria, wherc different compounds. Licbi g wa s awarded a doctorate ill absellfia in 1822. Througfl the patronage of Kastner, Li ebi g's dili gence and brilliance had _ already been brought to the notice of the Grand Duke of Hesse Also in this issue (page 5): Darmstadt and hi s ministers, who paid for Li ebi g to study chemistry in Pari s between 1822 and 1824. European Tick-borne infections In Pari s Li cbi g was greatly impressed by thc lcctures and Professor Marta Granstrom re sea rches of the French chemists Vauquelin ( 1763- 1829), Department of Cliniea l Mierobiology, Thenard ( 1777- 1857) and Gay-Lnssac ( 1778- 1850), with Karolinska Institute, Stoekholm, Sweden whom he came in to daily contact. Liebig becamc determined to transplant their teaching methods and insights on to German Ixodes ricinus - main vector of Lyme disease so il. While in Paris Li ebi g investi ga ted the dangerously in western europe Cu/tureVoil 9 No2 ••••••••••••••••••••••••••••••• The work on fulminates, together wi th <.l Inceting wi th the influent ia l Germ an traveller, A lexander von Humboldt ( 1769- 1859), who then lived in Paris and who was always on the loo k out for young tal ent, led LO Liebig's appointment La a Chair at the small uni versity ofGiessen in May 1824. As Liebig lalcr observed in a fragmentary autobiography, 'al a !m:1Jc r university. or ill a larger IOWIl. Illy energies would !/(fI'C been divided alld dis,\';paled, (lnd it \IIould have beell Above: Liebig's analytic;.1 laboratory (after:. drawing by Tr.llltschold). Right: I h" "me Pictu res counesy of Wilhelrn Lewicki. Liebigiana Ludwigshafen. Justus Liebig Society i /II/((.:h more difficult, perhaps impossible. 10 reach my goal.·2 This goal was to cxp'lIld and inst itutionalisc the lcaching - attracted by Liebig's techniques, reputation and the low fees of chemi stry (w hi ch hitherto in Germ an uni versiti es had made possible by the Hcssen government's subsidy of the been mere ly an adj unct of pharmacy For apo thecaries and laboratOly- Liebig had to expand his facilities and to syslematise medical student s) by placing it upon a thoro ughl y practi cal Lh e tndnillg he gave to students. Two or his students, Heinri ch (or laboratory) basis and by concentrating attention upon the Wi ll (18 12- 90) and Carl Remigills Freseni us (18 18-1897) were little-cult ivated arCH of organic chemi stry. As a teacher, cncouraged to publish tex tbooks on qualitative and quantitative Li ebig hnd initiall y conccntrated on pharmacy through a analysis whjch were translated into severaJ languages. Liebig's private school that the University authorities all owed hi m to Im-ge number or roreign students (on average at least ten every conduct as part of hi s professorial duties. This school was semester) also ensured ~1a t his emphasis upon laboratory-based eventually absorbed into the Philosophy FaculL y in the teaching and researc h was copied in other cOUlmies and Gelman 1830s. It was pharmacy and the difficul ties with th e analyses states-ror example, at the Royal College of ChemisLIy founded or th e alk aloids, that di rected Li ebig's atte nti on to thc need in London in 1845, and Hermann Kolbe's large laboratory at 10 speed tip and to sim plify th e basic copper ox ide techn ique Leipzig in Saxony in 1868.3 of organi c analysis th at he devised in 1830. The perfection Liebig remained 28 years in Giessen, where the Duke of of this method led to a decade of in tensive in vest igati on o f Hesse Drumstadt made hi m a Baron in 1845. in 1852, worn out org'.IIli c compounds by Li ebig and his students, Li ebig by teaching, he moved to the University of Munich where he no himself publishing an average of thi rty papers each year longer gave practical instnlcli on, but plirsued his own interests betwee n 1830 and 1840. Several of the se we re to be of the and did a great amount or popular lecturing and writing. greatest significance for the theory and practi ce o f organi c chemistry, nota bly an extensive series of papers on th e Farming nitrogen cont ent of bases, the joint work with Wohler on th e benzoyl radical ( 1832), and on the degradat ion products of Sickened by ted ious di sputes conceming the consLitlition of IIrea (1837), the discovery of chlora l (trichloroethanol, organic compounds, and cOllvi nced that orgrutic chenustry could 1832). the identilieati on of the eth yl radica l ( 1834), the be used as a tool to investigate ti ving processes, Liebig preparation of ace taldehyde (eth anol, 1835), and the abandoned pure chemj sLIy from about 1840 in an attempt to polybasic theory of organic ac ids (1838). solve aglicultural and physiological questions. in lhat year he The radical theOlY, together with growing experience of publi shed Die orgallische Chemie ill ilire,. Amvendllllg all! organic analysis, gave Liebig and Wohler the confidence to AgriclIlllIr IIlld Plly.\·;ologie (Braunschweig, 1840). Simul­ analyse urine betwecn 1837 and 1838 and to identi fy, anal yse taneously translated into Engli sh and French, thi s book sLI"Cssed an d classify its inllu merable constituents and degradation that because 'perfect agricullure is the tme foundation of aU products. such as urca (carbamide), uri c acid . allantoin and trade and indusuy ... a rati onal system of agricultm"C cannot be uramil. which they believed to be produced by 'innunlcrablc ronncd without U)Capplicalion of scientific principles.' Only the Ill l..:t amoqJhoscs' of uric acid - itselr a degradati on product, as chemist, he claimed somewhat dogmatically, could teIJ the thcy supposed. of nesh and blood. This magnirieen,t_ farmer the best means of feed ing vegetables, the nalure or the investigation.
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