Rediscovery of the Elements Courtois and

U originally used in his gas law experiments. Europe, on stable and barn stone walls, salt- Boyle was puzzled by the behavior of gunpow- peter grew in the form of "blooms" resembling der, which combusted in an evacuated jar just cotton tufts. Recent analyses show such a as it did in the open atmosphere, when heated growths of saltpeter are surprisingly pure, often 4 by the sun's rays concentrated by a magnifying greater than 95% KNO 3 . Saltpeter diggers- glass.' Boyle did not understand that saltpeter Salpetergraber in Germany or Salpetrier in

(known today to be KNO 3) contained its own French'-soon learned to excavate soil about "air." Carl Wilhelm Scheele (1742-1786) got his stables, pigeon cotes, manure piles, or barn- first hint of the nature of this supporter of com- yards to collect the saltpeter therein. bustion when he observed sparks as saltpeter As the demand for saltpeter increased, the was heated with oil, and he went on to discover saltpeter plantation/refinery was born, called oxygen.' Today we understand the basic reac- the Nitrarv (Nitriere in French, Nitriarv in

tion of gunpowder to be 2 KNO 3 + 3 C + S -> German); (Figure 1). The manager of a nitrary K,S + N + 3 CO .The evolved gases expand would lay down a stratum of lime and cover James L. Marshall, Beta Eta 1971, and 2 2 and serve as the propellant in rockets and guns.' with manure, garbage, corpses, and any other Virginia R. Marshall, Beta Eta 2003, Saltpeter (meaning "salt-rock") is the most organic material, including a periodic dowsing Department of Chemistry, University of soluble of the nitrates and wicks up rapidly in with the urine of "drinkers of wine or strong North Texas, Denton,TX 76203-5070, soil; it was first observed in China where a cli- beer."' The major qualification of a nitrary man- [email protected] mate of alternatively cold/hot wet/dry climates ager was his ability to tolerate the incredible allowed it to form on soil surfaces.' In Medieval stench of his enterprise. After a few months the saltpeter diggers unearthed copious amounts of Bernard Courtois (1777-1838) serendipi- saltpeter-rich soil. An aqueous washing of the tously discovered iodine in Paris while soil was reacted with ashes, filtered, concentrat- reacting varec (ashes of seaweed) with ed by boiling, and cooled to produce white sulfuric acid. He was using varec as a source of crystals of saltpeter. (Figure 2) potash (potassium carbonate), necessary in the manufacture of saltpeter (potassium nitrate) used in gunpowder.

The history of saltpeter. The 7th century Taoist alchemists in western China stumbled onto a concoction of honey, sulfur, and saltpeter which caused smoke, fire, sparks, and thunder BI -called huo yao, or "fire drug"- thought to be the elixir of life.1 We know the incendiary mix- ture today as gunpowder.2 By the mid-1200s, the Chinese discovery had spread to the Western world.' Roger Bacon 'i'r 1. Saltpeter works as shown in a 1-98 (1214-1294) of Oxford recognized it as a mix- woodcut." The rows of hills (C) were filled with ture of "saltpeter, sulfur, and charcoal" (prefer- manure, garbage, soil, blood, ash, and lime, and ably of hazelwood), with the saltpeter in were periodically soaked with urine. The nitroge- 2 excess. The Battle of Crecy in 1346, at the nous compounds released ammonia, which were beginning of the Hundred Years War, may be oxidized to nitrates. After a year or so the Figure 2. The refining of saltpeter in the shed marked as the formal introduction of gunpow- "ripened"saltpeterbeds were processed in the (1556).2 The "ripened" soil was leached in vat (B); der on the battlefield as "gonnes" were used "refinery,"thework shed (B) (see Figure2). The the filtered solution was drained through plug (C) beside the famous longbowmen.' bucket (A) collected rainwater. A cord of wood (D) into collection vat (D). This filtrate was concen- In an attempt to understand the nature of was used as fuel for the hearths in the shed. A trated on hearth (A), then poured into crystalliza- gunpowder, Robert Boyle (1627-1691) studied saltpeter digger (E) would remove soil "ripe"for tion buckets (E) with inserted copper sticks on gunpowder in a vacuum, generated by pumps processing. which saltpeter crystallized as the solution cooled.

72 THE HEXAGON/WINTER 2009 ical knowledge and laboratory experience at the Academie laboratory and at the nitrary.

Courtois in Paris. In 1798, Bernard Courtois 1' - became a laboratory assistant at the Ecole Polvtechnique, arranged by Morveau who had moved to Paris in 1791 to become a member of the Legislative assembly and also a professor at l'Ecole Polytechnique." At this time the cole Polytechnique was located in the Palais Bourbon, directly across the Seine from the Place de la Revolution, today la Place de la Concorde, where o - Lavoisier was guillotined in 1794.' At l'Ecole Polytechnique Bernard Courtois worked with Fourcroy and Thenard (the discov- erer of hydrogen peroxide, 1777-1857), then with Armand Seguin (1767-1835).7 Seguin is perhaps best known for serving as the human Figure 3. Southward view on Rue Monge in Dijon, (N47 19.12 E05 02.02). The Acaddmie de guinea-pig for Lavoisier's respiration studies; Dijon is to the left (51 Rue Monge); Courtois'home (where Bernard Courtois was born, 78 Rue Monge) is classic drawings by Mme. Lavoisier show him the gray building above the red automobile, just this side of the yellow half-timbered house. The Academie with the"gas-masks"in Lavoisier's laboratory at was founded in 1725 and moved to this Rue Monge location in 1772. (At this time, the street was called la Petit Arsenal.' In Seguin's laboratory Bernard Rue Ponternant).Dijon is 250 km southeast of Paris. worked with opium compounds, and apparent- ly isolated morphine, although not formally Today we understand the chemistry of the de Morveau (1737-1816), a lawyer and chemist acknowledged Seguin delayed publication and process. Ammonia released from organic mate- who founded the chemistry department at was scooped in 1804 by Friedrich Wilhelm 7 rial is oxidized to nitrates. The lime (CaO) keeps Dijon Academy. Guyton de Morveau is well Adam Serturner (1783-1841) of Paderborn, the pH 7-8 required by the nitrifying bacteria. known as one of the authors of the modern Germany, who gave the drug its modern name., The product, calcium nitrate ("lime saltpeter"), system of chemical nomenclature in 1787 (the In 1804, Bernard terminated his studies at is useless because it is hygroscopic and the others being Lavoisier,3 ' Claude-Louis l'Ecole Polytechnique, which was becoming resulting gunpowder would absorb moisture. Berthollet (1748-1822),3, and Antoine Fourcroy militarized upon Napoleon's edict and moved Hence, the calcium nitrate is reacted with ashes (1755-1809).^ In 1780 Jean-Baptiste was also to its new site near the Pantheon.' Bernard now (potash; potassium carbonate) to precipitate assigned manager of the new Saint Medard assisted his father, who had moved to Paris in the calcium salts and leave a potassium nitrate Nitrary in Dijon (1.7 km east, on the outskirts of 1802 to set up a nitrary and had settled on Rue solution: Ca(N0 3)2 (aq) + K2C0 3 (aq)-> town) (Figure 4), one of the government-spon- Saint Marguerite (today Rue Trousseau)," about CaCO3 (s) + 2 KNO 3 (aq).' sored plantations created to cope with the salt- 1 km northeast of the Seine on the outskirts of During the 1600s Great Britain found a peter shortage., As a boy the precocious town. Six years later, Bernard assumed owner- cheap source of saltpeter-the East India Bernard Courtois absorbed considerable chem- ship of his own nitrary another kilometer north Company could allow import of the commodi- ty from India at one-quarter of the domestic cost.' (Note 1) France continued to produce its saltpeter from its home nitraries and itinerant saltpeter gatherers, but by necessity had to pur- chase some of its supply from Holland at an exorbitant price. Louis XVI (1752-1793) estab- lished the Gunpowder Administration in 1775, and as manager he appointed Antoin-Laurent Lavoisier (1743-1794), who promptly increased saltpeter production and improved the gun- powder manufacture process.' This self-suffi- Ru d ciency would be vital when Great Britain block- aded France during the French Revolutionary Wars (1792-1802) and the Napoleonic War (1803-1815).

A E Courtois in Dijon. Bernard Courtois was born in Dijon, France, the son of a wine merchant Jean-Baptise Courtois (1748-1807?). The Figure 4. This is what remains of the largest and oldest (1582) plantation refinery in Dijon-the Raofinerie Courtois home was directly across the street des argentieres (N 470 19.01 E 050 03.25), formerly in the country, but now a residential neighborhood from the Academie de Dijon (Figure 3), where with no hint of the originalnitrary. In the early 1800s there were always several nitraries in every city. the father won the position of chemistry Saint Medard (which Jean-Baptiste Courtois owned) was 600 meters north (N 470 19.33 E 05 03.36). demonstrator, hired by Louis-Bernard Guyton Inset: Street sign expanded, "Street of the [saltpeter] refinery."

WINTER 2009/THE HEXAGON 73 on Rue Rue Saint-Ambroise (Figure 5), where down chemically, even in the presence of red- he remained 1810-1821. It was here that he hot carbon. discovered iodine. In these December papers and others that fotlowedj vigorous competition between Gay- The discovery of iodine. Potash was scarce I ussac and Davy developed into bitter con- because of the Napoleonic wars (1803-1815), lention about who should be credited with and Bernard Courtois had resorted to varec what. Duplicate claims were published, even imported from the Brittany and Normandy sea- wvith regard to who named the new element. coasts., One day in late 1811 while cleaning ;ay-Lussac said he should be credited for pots he accidentally discovered that concentrat- naming it "l'iode." However, Davy maintained ed sulfuric acid reacted with varec in an he correct name was iodine, in analogy to exothermic reaction to yield a violet cloud chlorine, which he had named in 1810 when he which condensed on a cold metallic or ceramic recognized its elemental nature." (Previously, surface in the form of crystals with the color Figure 5. This is the icew northward on Rue chlorine had been called "oxymuriatic acid," and luster of graphite.a Courtois performed Saint-Ambroise in northeast Paris (N 480 51.76 believed to be a compound of HCl and oxy- E 020 22.70). The home and some research on the crystals, and discovered a Saltpftriere of gen."') Fortunately, in spite of heated argu- Bernard Courtois where he discovered iodine, was fulminating powder when he reacted the dark ments about proper recognitions, it was agreed on the left, present address is 31 Saint-Ambroise crystals with ammonia-he had produced that Courtois, who could have easily been lost (old address 9), now the site of modern apart- nitrogen triiodide."' Not being a regular mem- in the shuffle, should be given credit for the ini- ments. The plantation measured roughly 100 x ber of the scientific establishment, he could not tial discovery."" 100 meters. immediately publish his findings. In May 1812 In 1815 the Napoleonic Wars were over, and he shared his experiences with his colleagues cheap Indian saltpeter became available.' Nicolas Clement (1779-1842) and Charles ic men in France, that no account of it was pub- Courtois turned his total attention to iodine, Bernard Desormes (1771-1862), two scientists lished till the arrival of our English philosopher and with the help of Clement and Desormes from Dijon who had studied at l'Ecole there."6 developed methods for extracting iodine from Polytechnique when Bernard was there. One who reads these December papers of seaweed in quantity." By 1820, the medicinal Unfortunately, they were slow in their analysis Annales de Chimie8 can begin to appreciate the properties of iodine had become known and of the new substance and did not report it to fascination and confusion of the chemists as Courtois became a commercial manufacturer. the Academie for 18 months. they tried to comprehend this"substance nou- In 1831, he was awarded the Montyon Prize by Sir (1778-1829) of London velle"-this was half a century before the l'Acad6mie for his contributions to medical sci- embarked on a two-year scientific tour of Periodic Table and the concept of chemical fam- ence, but he never benefited financially from Europe in 1813, and because of his fame ilies. Iodine was difficult to categorize: It was his discovery and he died penniless." Napol6on granted him special permission to very strange because it had the physical On November 9, 1913, the scientific com- travel through France. While in Paris (October appearance and the heavy weight of a metal, munity commemorated in Dijon the 100th 15-December 23, 1813) Davy was given a but it dissolved in ether!' It behaved like oxy- anniversary of the discovery of iodine by hold- sample of Courtois' "substance nouvelle" gen or chlorine because it reacted with met- ing a banquet at the Dijon Academie and 8 which he analyzed using the traveling labora- als.8b c In fact, because of its odor, a iodine was mounting a plaque on the old Rue Monge tory chest he carried on all his journeys. originally thought to contain chlorine.8 " house (Figures 6 and 7).10 No bust or portrait Joseph Louis Gay-Lussac (1778-1850), a However, it was found to react with hydrogen was prepared for the celebration, because no member of the elite Societ6 d'Arcueil who gas to form not hydrochloric acid but a new likeness of Courtois was known," just as for 8 had formulated the law of combining vol- acid (hydroiodic acid), " c proven by its reaction Smithson Tennant (the discoverer of osmium 3 umes,8b was motivated by this British intruder with lead and silver nitrate to form unknown and iridum) d (Note 2). to initiate his own research. In a few weeks the yellow salts (instead of white).8 a Ultimately, it two scientists had conducted detailed inde- was decided that it must be a "corp nouveau" (a References. pendent studies on this substance which had "new body")'c because it could not be broken 1. J. Kelly, Gunpowder, 2004, Basic Books previously been shelved for 11/2 years. (Perseus Books Group), NY. In December of 1813 there appeared8 in 2. J. R. Partington, A History of Greek Fire and Annales de Chimie (the prestigious journal of the Gunpowder, 1999, Johns Hopkins University Academie des Sciences) several back-to-back Press, Baltimore MD. papers on "une substance nouvelle dans le 3. J. L. Marshall and V. R. Marshall, The HEXA- Vareck" (a new substance from varec), which GON of Alpha Chi was called "l'iode" from the Greek word for Sigma, (a) 2005, 96(1), 8-13; (b) 2005, 96(1), 4-7; (c) 2006, 97(4), "violet." These articles were authored by 50-55; (d) 2009, 100(1), 8-13. Courtois,la Gay-Lussac,"b and Davy 8c (Courtois' paper was read by Cl6ment, since Courtois was 4. U. Bretcher,"Ulrich Bretscher's Black not a member of the Acad6mie; he was identi- Powder Page,"http://www.musketeer.ch/black- fied only as a lowly "salpetrier from Paris"'a). Figure 6. This photograph uicwmiig northward on powder/ saltpeter.html. Reflecting tensions between France and Great Rue Monge was taken on the 100th anniversary 5. U. Bretcher, personal communication, Britain, the (London) Royal Society delighted in of the discovery of iodine (9 November 1911).6 Consulting Engineer, Kuster and Hager, noting (20 January 1814) that:"b The Academy is to the right; the crowd is facing Uznach, Switzerland. "[Iodine] was discovered about two years left at the home of Courtois, where a plaque is 6. L. G. Toraude, Bernard Courtois et la ago; but such is the deplorable state of scientif- being mounted. Dicouverte de l'Iode, 1921,Vigot Freres, Paris.

74 THE HEXAGON/WINTER 2009 PRDFFESIDNAL NEWS

Staying Active in Chemical vanilla into a big pot, added liquid nitrogen, stirred with a big wooden spoon, and had deli- Outreach After Children cious ice cream that they could all try in less E.ST N" 8 -V91Ei777 By Matt & Jen Schnippert, Gamma Beta 2003 than two minutes. It was so much fun, we - NAMAClEN 3RNA COURTO'S used our leftovers to make it at the chapter -m cC vrwu - r t'IODL Since my wife, Jen, meeting that evening. My girls liked it so and I had our first child much that when I brought home the Dewar less than a year after after a magic show later this summer, Kaia, my our initiation, it has two-year-old, pointed at the container and Figure 7. Plaque on the Courtois home. been difficult to remain asked "ice cream?" I then, as any well-trained active in the Fraternity. Translation:"In this house was born on 8 parent would do, went out to the store to get Last February 1777 the pharmacistBernard Courtois summer, however, the necessary ingredients to make it. who discovered iodine in 1811." we were able to include our eldest child, Liisi, in GE Note: The GE never misses an opportunity our outreach activities. to point out that he has the distinct pleasureof hav- 7. P. A. Swain, Bull. Hist. Chem., 2005, 30(2), She was actually the ing the first journal reference on the liquid nitrogen 103-111. source of one of the ice cream demo (J. Chem. Educ. 1994, 71, 1080). 8. (a) B. Courtois, Ann. Chim., 1813, 88, activities. This past Following from some patents on creating machines 304-310; (b) J. L. Gay-Lussac, op. cit., spring, one of her to prepare instant ice cream, which the GE has NO 311-318, 319-321; (c) H. Davy, op. cit., friends' fathers, a grad- Kaia Schnippert part of there is at least one cafr that has opened in 322-329. uate student in her- Chicago that features liquid nitrogen ice cream (http://www.icreamcafe.com/). 9. J. R. Partington, A , petology, brought in some reptiles to show her 1961, Vol. IV, Macmillan, London (a) 51-57, class at the on-campus preschool. All evening (b) 85-90; (c) 636. after coming home, all Liisi could talk about was how she wanted her mommy and daddy to ACS & Alpha Chi Sigma 10. C. Guyotjeanin, Revue d'Histoirede la Pharmacies, 1995,,42(2), 117-123."Le come to school so she could be a helper like her Luncheon friend had been. Because I had participated in a Souvenir de Bernard Courtois,"kindly The regular Alpha Chi Sigma luncheon was number of Gamma Beta's magic shows, I talked furnished by Dr. Michel Pauty, President de held during the 238th ACS National Meeting to our chapter's Master Magician, and to Liisi's l'Academie des Sciences, Arts et Belles- on Tuesday, August 18, 2009 from 11:30 am- school's director, and set up a date Lettres de Dijon. to perform a 1:00 pm at Chan's Mongolian Grill and Tokyo magic show. 11. O. Guttman, Monumenta Pulveris Pyrii, Sushi, 1207 9th Street NW, in Washington, D.C. I've performed a number of magic shows, 1966, London. In attendance: Gary Anderson, Alpha Eta 1962, most of which were for school-aged children, James Hammond, Pi 1947, Brenda Wray, Delta 12. H. L. and L. H. Hoover, English translation but Liisi's class was made up of children rang- 2003, Sarah Steinhardt, Alpha Epsilon 2003, Walt of G. Agricola, De Re Metallica, 1912, ing in age from 3-5. In our usual magic shows, Benson, Eta 1956, Larry Dusold, Rho 1967, John London; 1950 edition., Dover, NewYork. we try to provide the kids with reasonably thor- E. Adams, Beta Delta 1971, Carol A. Deakyne, ough explanations of things, even if the mater- Notes. Delta 1994, Sherrie Settle, Alpha Kappa 1983, ial goes over their head. We hope that by expos- Kenneth L. Busch, Epsilon 1984, Jim Walsh, Beta Note 1. Later, when Indian saltpeterbecame ing them to the real explanations (and not Nu 1957, William Gleason, Beta Omicron 1966, excessively expensive, Chilean saltpeter could be oversimplifications), it will pique their curiosity Allan Walters, Beta Phi 1972, Rolf Renner, Beta exploited. However, this South American commod- and inspire them to learn more. With this age Pi 1961, Sally Mitchell, Pi 1980, Elizabeth group, however, I knew immediately I would ity is mainly sodium nitrate, which is inferior Mitchell, Pi 2009, Joe Contrera, Alpha Rho 1984, because it is hygroscopic.' Bird and bat guano have to stick to demonstrations that were flashy Adam Hopkins, Gamma Beta 2000, Candie have also been rich sources of ammonia. With the and exciting, leaving detailed explanation for a Paulsen, Beta Nu 2003, Dawn Mason, Delta development of the Haber process (the combina- few years down the road. 1990, and Howard McLean, Iota 1989. 0 tion of nitrogen and hydrogen gas to form Several of the experiments we did were old ammonia by Fritz Haber 1868-1934) in 1913,9 standbys we'd done often at our museum there was no further need for organic sources of shows-bubbling dry ice in colored water, dry ammonia for the munitions industry. ice balloons, shattering a ball and flower with liquid nitrogen, and-the perennial favorite- Note 2. Careful research by French historians, elephant toothpaste. Because I had more free- including detailed interviews with descendants, dom to work outside the box, I decided to try has verified that no drawing, painting, or other something we've never done before and made likeness has survived of Bernard Courtois.' liquid nitrogen ice cream. I found a recipe However, recently a photograph(!) of Bernard online and made sure to try it at home before Courtois has been posted on Wikipedia which is doing it in front of the kids (we wouldn't want nonsense for such an early date. The authors are to embarrass ourselves in front of my daugh- working to correct this error which has been ter's class, after all), but it makes some of the repeated on several websites. This cautions one to best tasting ice cream I've ever had. It doesn't be very wary of information on websites, even the last long or freeze well, so you need to careful- usually reliable Wikipedia, which contain much ly gauge how much you need. The kids were Brothers at the Alpha Chi Sigma luncheon at the unverified and redacted material. all amazed when I poured cream, sugar, and Washington, D.C., ACS Meeting.

WINTER 2009/THE HEXAGON 75