Spring meeting of the Illinois Association of Chemistry Teachers

C. Hockett and Professor T. L. Davis, both of the. Massachusetts Institute of Technology, he also wishes to make grateful acknowledgment for innumerab...
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glucose) is the complement of Dubrunfaut's and the two must cause chemists the world over t o be grateful to French science, because more fruitful single diswveries in the chemistry of the carbohydrates have hardly been made."

He was a member of numerous scientific societies and a Knight of the Legion of Honor. Dubrunfaut's second most important discovery was that of fructose. He early recognized that invert sugar was a mixture of two sugars and in 1847 he isolated (7) the insoluble lime addition compound of fructose from which on careful treatment with oxalic acid he obtained a sirup of fructose which he called "glucose l6vogyre." Later he obtained fructose from a number of fruit juices as well as by the hydrolysis of inulin (8). He showed the close relationship between glucose and fructose by measuring the quantities of alcohol and carbon dioxide produced by each upon fermentation. At the time there was great scepticism among scientists concerning his discovery. Over a period of years after the original work he demonstrated the procedure before a number of doubting savants, among whom were Melsens, Stas, pussy, Kuhlmann, and Magnus (9). Finally in 1856 be carefully repeated his work on the isolation of fructose and published explicit directions for the procedure. Although he obtained fructose in an undoubted state of purity he was never able to crystallize it. From the rotations of glucose, fructose, and invert sugar be showed that the latter was an equimolecular mixture of the former two. It is somewhat odd that so keen an observer as he seems never to have observed the mutarotation of fructose, but perhaps this is explainable by the facts that he had only a sirup and that fructose is one of the most rapidly mutarotating sugars.

Dubrunfaut should be remembered as one of the first to isolate and characterize the disaccharide maltose. DeSaussure in 1819 (10) had obtained maltose in a very doubtful state of purity, and it is questionable whether he recognized it as a single compound. In 1847, however, Dubrunfaut isolated a compound from the diastatic reaction of malt on starch and named it maltose (11). Here, again, although he took the specific rotation of his product he appears to have missed completely its mutarotation. Like DeSaussure's discovery, Dubrunfaut's was completely forgotten, and i t remained for O'Sullivan in 1872 (12) to rediscover this important sugar. On October 7, 1881, Dubrunfaut died a t Bercy-a renowned industrial chemist and teacher, famous for his contributions to the beet-sugar and alcohol industries of France but even himself never aware of the importance of his discovery of mutarotation. His burial was in harmony with the tenor of his life, for he decreed in his will that his funeral should be simple and quiet, the expenses which would have gone to the usual flowery affair to be given to the poor.6 ACKNOWLEDGMENT

The writer wishes to express his sincere appreciation to Professor E. 0. von Lippmann for his kind aid in finding a photograph of Dubrunfaut. To Professor R. C. Hockett and Professor T. L. Davis, both of the Massachusetts Institute of Technology, he also wishes to make grateful acknowledgment for innumerable kind suggestions.

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DAVIS,"Dubmnfaut and His Work, 1797-1881," Chemistry Industry, 49, 644 (1930). This is an excellent sketch of his life as well as a particularly valuable review of his chemical works.

GENERAL BIBLIOGRAPHY

GLAESER,"Biographie nationale des contemporains." Glaeser e t Cie., Paris. 1878, p. 203. VON LIPPMIINN, "Gescbichte des Zuckers." Leipzig, 1890. POGGENDOR~F, "Biographisch-LiterariscksHandwiirterbuch." Barth. Leipzig hd. 3, 1898, p. 383.

"Histoire centenalle du sucre de betterave." Paris, 1 9 1 2 (le S y n d i c a t d e s f a b r i c a n t s d e s u c r e d c France)' Also those works whose title pages are reproduced.

LITERATURE CITED

"Catalogue de la precieuse collection d'autographies composant le cabinet de feu M. A.-P. Dubrunfaut, chimiste, nffirier la T.eeion Printed in Paris on the --.... de -. . -- - d'honneur." occasion of the nublic sale of this part of Dubrunfaut's estate on ~ a r c h i 51885. , "ON LIPPXANN, "Vor hundert Jahren N," Dezrt. Zuckerind.,

(5) Compt. rend.. 42, 228 (1856). (6) Ibid., 42, 739 (1856). (7) Ibid., 25, 308 (1847). (8) Ibid., 42, 739 (1856). (9) Ibid., 42, 901 (1856).

SPRING MEETING OF THE ILLINOIS ASSOCIATION OF CHEMISTRY TEACHERS The annual Spring Meeting of the Illinois Association of Chemistry Teachers will be held a t Springfield, Illinois, on Saturday. April 6, 1940. The morning session will be devoted to inspection trips to two of the newest state laboratories, the

highway and bacteriological units. The luncheon and afternoon business and professional program will be held a t the Spri&eld Junior College. Dr. John C. Hessler, James Millikin University. Presidentof the Association, will preside.