On Labarraque's Disinfecting Soda Liquid. [1827. 



were then heated nearly to the boiling-point, air being con- 

 tinually passed through. In this way all the chlorine which 

 had combined with the carbonated alkali without decomposing 

 it, was set free by the sulphuric acid, and carried off by the 

 current of air and vapour, whilst any which had acted chemi- 

 cally upon the alkali would, after the action of the sulphuric 

 acid, be contained in solution as muriatic and chloric acids, 

 and from the diluted state of the whole, would not be removed 

 by the after process, but remain to be rendered evident by 

 tests. The other portion being diluted, had sulphuric acid 

 added also in excess, but no attempt was made to remove 

 the chlorine. Equal quantities of these two portions in the 

 same state of dilution were then examined by nitrate of silver 

 for the quantities of chlorine sensible in them, and it was 

 found that the latter portion, or that which retained the whole 

 of the chlorine thrown into it, contained above sixty times as 

 much as the former. 



12 Now although it may be supposed that in the former 

 portion that part of the chlorine which, in acting energetically, 

 had produced chloric acid, could not be detected by the nitrate 

 of silver, yet more than a sixth of the small portion which 

 remains cannot be thus hidden ; and even that quantity is 

 diminished by the sulphuric acid present in excess, which 

 tends to make the chlorine in the chlorate sensible to nitrate 

 of silver : so that the experiment shows that nearly 59 parts out 

 of 60 of the chlorine in M. Labarraque's liquid are in a state of 

 weak combination with the carbonated alkali, and may be sepa- 

 rated by acids in its original condition ; that this quantity is 

 probably wholly available in the liquid when used as a bleaching 

 or disinfecting agent ; that little, if any, of the chlorine forms 

 chloride of sodium and chlorate of soda with the alkali of the 

 solution ; and that the portion of chlorine used in preparing the 

 substance which is brought into an inactive state, is almost in- 

 sensible in quantity. 



13. The peculiar nature of this compound or solution, with 

 the results Mr. Phillips had shown me (8), obtained by evapo- 

 ration of a similar preparation to dry ness, induced me to try 

 the effects of slow evaporation, crystallization, heat, and air 

 upon it. In the first place, five equal portions of the solution 

 prepared by myself were measured out : two were put into 



