732 ANNUAL REPORT SMITHSONIAN INSTITUTION, 19 2 8 



cal Chemistry Applied to Toxins and Antitoxins," Madsen was 

 responsible for the experimental methods, Arrhenius for the theoreti- 

 cal treatment. They maintained that the toxin-antitoxin combina- 

 tion (held by Ehrlich to be a firm chemical union) wa,s in reality 

 reversible, and governed by the ordinary mass-action law. The 

 immunological phenomenon of antitoxin action was likened to the 

 interaction of a weak acid and a weak base, such as boric acid and 

 ammonia, which only partly neutralize each other. The work con- 

 stitutes a classical study among the early researches into the under- 

 lying nature of immunity phenomena, and contributed to laying the 

 foundation of " immunochemistry," a term first applied by Arrhenius 

 himself to a branch of biological research in which reactions of 

 markedly specific character occur between biological principles of 

 unknown chemical nature. Arrhenius pursued this tj^pe of research 

 for a decade, and published two books dealing with it, Immunochem- 

 istry in 1908, and Quantitative Laws in Biological Chemistry in 

 1915. 



In the year 1905 Arrhenius happened to be in Berlin and was asked 

 by the university adviser of the Prussian IMinistry of Education if 

 he would be inclined to accept a position in the Prussian Acadamy, 

 similar to that held by van 't IToff. This was a very tempting pro- 

 posal, but Arrhenius, with his usual patriotism, requested time to 

 consider it, and asked and was granted permission to speak of it to 

 the Minister of Education in Sweden. It had been the intention of 

 the Academy of Sciences to found a Nobel institute for chemistry 

 and one for physics, but the wish having been expressed by King 

 Oscar II that Arrhenius should not be allowed to leave Sweden, 

 the academy resolved to found forthwith, instead of the two pro- 

 posed institutes, a Nobel institute for physical chemistry, and of this 

 new foundation Arrhenius was appointed director. It was housed 

 at first in temporary quarters in Stockholm, but at Experimental- 

 fjiltet, a pretty park in the neighborhood of the town, a small labo- 

 ratory was erected with an official residence attached. The laboratory 

 was inaugurated in 1909. Here, with an assistant and a few re- 

 search workers as guests, Arrhenius could work and write under 

 ideal conditions on such problems of physical chemistry, physiologi- 

 cal chemistry, immunochemistrj', meteorology, and cosmic physics 

 as might please him. 



The stormy period of Arrhenius's career w^as now definitely over, 

 and from the time of his appointment to the Nobel Institute life 

 went very smoothly with him. From being a scientific outcast in 

 Sweden he became a scientific oracle, known and respected by all 

 classes of the people. 



He himself did little practical work in the new laboratory, but 

 stimulated and encouraged others. One of his chief pleasures was 



