84^ Mr. Faraday'5 Experiments on the Nature of 



Experiments on the Nature of Labarraque^s disinfecting Soda 

 Liquid. By M. Faraday, F.R.S., Corn Mem. R. Acad. 

 Sciences, Paris, &c. &c. 



1. The following experimental investigations relate to the 

 nature of that medicinal preparation which M. Labarraque has 

 lately introduced to the world, and named Chloride of oxide of 

 Sodium. They were occasioned by the accounts which were 

 given of this and other substances of similar power, to the 

 members of the Royal Institution, at two of their Friday even- 

 ing meetings * ; the value of the preparation, the uncertainty 

 of its nature, and the inaccuracy of its name, all urging the 

 inquiry. 



2. In the first instance the inquiry was directed to the na- 

 ture of the action exerted by chlorine gas upon a solution of 

 carbonate of soda, questions having arisen in the minds of 

 many, whether it was or was not identical with the action ex- 

 erted by the same gas on a solution of the caustic alkali, and 

 whether carbonic acid was evolved during the operation or not. 

 Chlorine gas was therefore carefully prepared, and after being 

 washed was sent into a solution of carbonate of soda, in the 

 proportions directed by M. Labarraque ; i. e. 2800 grains of 

 crystallized carbonate of soda were dissolved in 1.28 pints of 

 water ; and being put into a Woulfe's apparatus, two-thirds of 

 the chlorine evolved from a mixture of 967 grains of salt with 

 750 grains of oxide of manganese, when acted upon by 967 

 grains of oil of vitriol, previously diluted with 750 grains of water, 

 were passed into it ; the remaining third being partly dissolved 

 in the washing water, and partly retained in the open space of 

 the retort and washing vessel. The operation was conducted 

 slowly, that as little muriatic acid as possible might be carried 

 over into the alkali. The common air ejected from the bottle 

 containing the solution was collected and examined; but from. 

 the beginning to the end of the operation not a particle of car- 

 bonic acid was disengaged from the solution, although the chlo- 

 rine was readily absorbed. Ultimately a liquid of a very pale 



« See the last volume of this Journal, pp. 211, 460. 



