Cause of the peculiar Condition of Iron. 257 



that the chemical relations of a body are, more or less, modi- 

 fied also as often as a change of its cohesive state is effected. 

 Sulphur for instance, in its peculiar (viscid) condition, phos- 

 phorus being liquid at the common temperature, selenium 

 in its half fluid state, carbon as diamond, all these simple 

 bodies are, most likely, in a chemical point of view, different 

 from what they are in their usual condition. We certainly 

 want as yet tests to ascertain the chemical difference which 

 exists, for instance, between viscid and common sulphur, &c. ; 

 but though this be the case, analogy, I think, makes up for 

 that want, and allows of our making an assertion of the 

 kind. There are, indeed, many instances in chemistry which 

 show a most intimate connexion existing between the cohe- 

 sive state of a body and its chemical relations, and it would 

 be quite superfluous to cite any such example. 



Now, if by means of heat, and in some rare cases by that 

 of light too, a number of simple substances can undergo an 

 essential change as to their molecular aggregation, why should 

 an agency so powerful as current-electricity, which parts 

 asunder elements most intimately combined with one another; 

 — I ask, why should such a force be incapable of modifying the 

 natural cohesive state of bodies, for instance, that of iron ? 

 The conjecture, that the current which passes from that metal 

 into a solution of blue vitriol modifies the molecular consti- 

 tution of iron so as to destroy the affinity of the latter for the 

 oxygen contained in the oxide of copper and disengaged from 

 water by electrolytic action, is indeed a new and rather a bold 

 one, but I should think no more so than many other conjec- 

 tural views, which are now much in vogue with chemists and 

 considered as very plausible. The fact that iron once being 

 rendered inactive does not remain in its peculiar condition, is 

 no proof against the correctness of my idea ; for it may be 

 said, that the modification of the molecular constitution caused 

 by the current is, as it were, a condition forced upon the metal, 

 a strained state, which ceases to exist as soon as its cause 

 ceases to act. The condition may properly be compared to 

 that in which the particles of a bent steel-spring exist. 



The circumstance that inactive iron can remain untouched 

 for any length of time within nitric acid of a certain strength 

 without the agency of a current, is a fact which may appear 

 to be quite irreconcilable with my hypothesis. I do not think, 

 however, that such is the case. In the first place we must 

 suppose that something like a " vis inertia " comes into pla}'-, 

 that is to say, to a certain degree a tendency of the iron par- 

 ticles to remain in their newly assumed juxtaposition ; but on 

 the other hand we must also admit the existence of some ac- 



Phil.Mag. S,3. Vol. 13. No. 82. Oct, 1838, S 



