A.:^,Ka 



THE 



AMERICAN JOURNAL OF SCIENCE. 



[THIRD SERIES.] 



Art. XLVI. — On the Destruction of the Passivity of Iron in 

 Nitric Acid by Magnetization ;* by Edward L. Nichols and 

 W. S. Franklin. 



I. 



During the winter of 1884—85, the authors of this paper 

 were engaged in the investigation of the chemical behavior of 

 iron in the magnetic field. In the course of their experiments 

 a beaker containing powdered iron, submeiged in cold concen- 

 trated nitric acid, was placed between the poles of a small 

 electro-magnet. While in the magnetic field the iron was 

 touched with the bulb of a thermometer, used in the determin- 

 ation of the temperature of the acid, whereupon it lost its 

 passivity and the solution burst into violent effervesence. The 

 reaction continued until the beaker was removed from the field, 

 when the iron again became passive. This change of condition 

 was found to be due to the action of the magnet, occurring 

 instantly in solutions of high temperature or of small degrees 

 of concentration, and taking place upon stirring in the field, 

 even in the case of iron in cold, concentrated acid. The fur- 

 ther study of this phenomenon, of which brief mention has 



* Paper read before the Kansas Academy of Science, November, 1885, with, a 

 supplementary note of later date. 

 Air. Jour. Sci.— Third Series, Vol. XXXIV, No. 204.— Dec, 188T. 

 28 



