313 Kirw anion Society of Dullin . 



received a distinct shock : at this time I stood on the stony 

 bank, in the bed of the river, and the apparatus was placed 

 on the rock, so that the Galvanic fluid was conveyed through 

 the rock, and the moist earth and stones on the bank. 



KIRWANIAN SOCIETY OP DUBLIN. 



March 10. A paper *' On certain Combinations of the 

 Oxymuriatic Acid, with Observations and Experiments on 

 their respective bleaching Powers," was read by S. Witter, 

 Esq. 



The paper commenced with stating the methods of pre- 

 paring the oxymuriates of lime, potash, and magnesia, for 

 the purposes of commerce : the formation of the dry oxy- 

 muriate of lime on the large scale, with analytical experi- 

 ments on its composition, was particularly detailed. To 

 ascertain the proportions synthetically of the constituent 

 principles of oxymuriate of lime, the oxymuriatic gas was 

 detached from its combination, and received through a sa- 

 turated solution of common salt : the analysis was calcu- 

 lated from the weight gained by hydrate of lime during its 

 conversion into the oxymuriatic salt, compared with its 

 weight previous to that operation. Corroborating the cor- 

 rectness of the analysis, tivo proportions of lime were uni- 

 formly found combined with one of oxymuriatic gas, in a 

 solution of that efTective bleaching agent. The application 

 of Sir H. Davy's views of the riature of chlorine and mu- 

 riatic acid, to Mr. Dalton's analysis of oxymuriate of lime 

 (described in Dr. Thomson's Annals), harmonized the 

 composition of Mr. Dalton's oxymuriate with that stated 

 in Mr. Witter's experiment: and this circumstance was 

 supposed to favour an opinion which the latter had ad- 

 vanced ; namely, that the bleaching strength of the oxy- 

 muriates was inseparably connected with the presence of 

 an excess of base, and that the real bleaching oxymuriates 

 i??. solution resemble that class called sub-salts. The neu- 

 tral oxymuriate of potash was found capable of being re- 

 stored to its original maximum of strength, by the addition 

 of a slight excess of alkali. 



All attemp.^ to prepare the oxymuriate of magnesia in a 

 dry form were stated as unsuccessful, and the liquid ob- 

 tained in the direct way was found to be too expensive, and 

 tedious in preparation, for general use. 



The decomposition of muriate and sulphate of magnesia 

 in the mother liquor of salt works, the former by heat, and 

 the latter by charcoal, was suggested as an oeconomical 



process 



