272 E. L. Nichols — Chemical Behavior of Iron 



/Si0 3 — Na. 

 Al-Si0 4 =Al 



y Si0 4 =Na 3 ci. 



Al-Si0 4 =Al Al-Si0 4 =Al .Si0 4 =Na 8 H 



/Si0 4 =Na 8 )Si0 4 =Na 2 Al-Si0 4 =Al 



Al-Si0 4 =Al AlfSi0 4 =Al x Si0 4 =Al 



)Si0 4 =Na 2 X Si0 4 =Na 3 . 



Al^-Si0 4 =Al +3H 2 0. 



X Si0 3 -Na. 



Nephelite. Sodcdite. Hydronephelite. 



These formulas express with decided clearness, the natural 

 order of transition from one species to another. The alteration 

 of a mineral necessarily involves the passage from a less stable 

 to a more stable condition ; and in this instance we observe 

 precisely that state of affairs. From a quite complex and 

 therefore easily disturbed molecule, through an intermediate, 

 simpler compound, we pass to one which is simplest of all, and 

 hence, presumably the most stable. I do not deny that such 

 formulas are subject to criticism, and that possibly the advance 

 of knowledge may brush them to one side; and yet I feel justi- 

 fied in claiming that they have some real value in the coordin- 

 ation of observed facts, and that, through their singular sugges- 

 tiveness, they assist in the prosecution of research. 



Laboratory TJ. S. Geological Survey, Washington, 1886. 



Art. XXYI. — On the Chemical Behavior of Iron in the Mag- 

 netic Field ; by Edward L. Nichols, Ph.D. 



[Read at the Ann Arbor meeting of the American Association for the Advance- 

 ment of Science.] 



When finely divided iron is placed in a magnetic field of 

 considerable intensity and exposed to the action of an acid, the 

 chemical reaction differs in several respects from that which 

 occurs under ordinary circumstances. The cause of one such 

 difference may be found in the fact that the solution of iron in 

 the magnetic field is in a sense equivalent to its withdrawal by 

 mechanical means to an infinite distance. Mechanical removal 

 requires the expenditure of work and the same thing is doubt- 

 less true of what might be called its chemical removal. In 

 other words the number of units of heat produced by the chem- 

 ical reaction should differ, within and without the field, by an 

 amount equivalent to the work necessary to withdraw the iron 

 to a position of zero potential. Experiments upon this point 

 which have been briefly described in a note already published 



