JULY. 1951
0
JOHAN ARVID HEDVALL RALPH E. OESPER University of Cincinnati, Cincinnati. Ohio
Carpova non agunl &i ,flicida, a dicbum that probably came down from .iristot,le, was generally acrepted until well into the twent,ieth cent,ury. I t has now been disproved, and especially by J. Arvid Hedvall. This eminent chemist was born a t Skara, Sweden, on January 18, 1888. His training was received primarily a t the University of Upsala, where he was assistant in meteorology (1909-1912) and then in chemistry (1912-1915). -4fter a. period of further study at Gottingen (1916) he carried on industrial research (catalysis) a t the metallurgical works at Falun. From 1918 to 1927, he was lect,urer a t the Technical High School in Orebro, and from 1927 to 1946 he m-as professor of chemical technology at Chalmers Universit,y of Technology in Gotehorg. Since 1946 Dr. Hedvall has been director of the Swedish Research Institute for Silica Chemistry, which was erected for him a t Goteborg by the state in cooperation with the industries. He was the first to demonstrate the fallacy of the Aristotelian declaration, and proved the possibility of reactions between solids in general. The start of this important advance is found in his doctoral thesis (1915): "On the reaction products between cobalt oxides and other metal oxides." In conjunction with about 150 collaborators in all he has since made systematic investigations of the reactivity of solids and its dependence on various factors, such as transition st,ates,
magnetism, electrical polasizatioq and irradiation. These influences, whose existence was established for the first time in most cases, have widened and deepened the scope of magneto-, electrc-, photo-, and phonochemistry. A new area, known as mineralography, was thus founded and worked out, with concurrent enrichment of the older metallography. The findings have been applied to a11 sorts of technical processes involving solid substances, especially many branches of silica chemistry, metallurgy, and industries employing catalysts. The restoration of museum specimens, cultural monuments, and buildings has profited from this research. The great effect exerted by dissolved gases on the reactivity of all sorts of solid solvents (known previously only for met:als) has been demonstrated and its importance thus emphasized. An excellent compilation and discussion of this new knowledge is given in Hedvall's book, "Reaktionsfahigkeit fester Stoffe" (Leipzig, 1938; reprinted, Ann Arbor, 1943). Professor Iledvall holds membership in various academies of science, and has received honorary degrees. He has lectured by invitation in most European countries, Turkey, Palestine, and the United States. He holds the Bjorken Prize (Upsala); the Goteborg Medal for Civil Merits; hhe Gauss Medal of the Rrunswick Societ,~ of Science.
