424 M. Balard on a pecuUar Substance [Dec. 



If I have not been deceived as to facts which I have related, 

 they fully authorise, as it seems to me, the opinion which I have 

 stated as to the nature of brome, and which has served me in 

 explaining its combinations. 



Any substance which, in its separate state, so effectually 

 resists, as brome does, all attempts to decompose it ; which is 

 expelled by chlorine from all compounds of which it forms a 

 part, and always appearing with its original qualities ; which, 

 acting upon the combinations of iodine, always replaces that 

 substance, to produce corresponding effects in the new com- 

 pounds ; which, notwithstanding this opposition of chemical 

 action, is associated with chlorine and iodine by well supported 

 analogies, seems, on these accounts, to possess the same claim 

 to be considered as a simple body. 



If this opinion should acquire confirmation by the subse- 

 quent examinations to which chemists may subject brome, the 

 rank which it ought to occupy among simple bodies is between 

 chlorine and iodine ; it will not be uninteresting to see two 

 substances so nearly allied as chlorine and iodine, admitting a 

 new body between them, and serving, by more intimate relations, 

 to connect a group of agents, the first two of which are already 

 so remarkable. Such an approximation of properties and che- 

 mical relations between these three simple bodies will acquire 

 additional importance on account of their common origin. 



Whilst at the commencement of my researches, in examining 

 the several combinations of brome, I almost always found in 

 them the strongest points of resemblance with the analogous 

 compounds of chlorine ; I confess I felt some scruples in admit- 

 ting brome to be a peculiar substance ; but these scruples have 

 not been able to withstand the power with which chlorine sepa- 

 rates it from its compounds, while brome separates iodine from 

 its combinations. 



I shall not conceal how much the materials which I have 

 been able to collect in order to trace the history of brome have 

 left still to be desired. I should indeed very willingly have 

 deferred their publication until more numerous researches had 

 allowed of my leaving fewer blanks, if I had not thought it 

 would be more useful in this important object of research to 

 direct the attention of those chemists to it, who possess more 

 power clearly to elucidate the subjects of which they treat. 



I do not for my own part intend to discontinue my attention 

 to this substance, as soon as the waters of our salt springs are 

 sufficiently concentrated to admit of my conveniently separating 

 the brome from them, especially if this sketch should be so for- 

 tunate as to interest the Academy ; and if fresh efforts should 

 yield me results of sufficient importance, 1 shall hasten to sub- 

 mit them to it, and shall do it with the most perfect confi- 

 dence. 



