Dr. Beck on the Chlorides of Soda, Lime, fyc. 253 



carbonate ; and should be kept at the temperature of 60° F. 

 or below. Having now adjusted to the mouth of the flask, 

 a bent tube, with one leg passing to the bottom of the vessel 

 containing the solution, the heat of a lamp or of a few coals 

 is to be applied to the flask. By this means chlorine is evolv- 

 ed and is absorbed by the solution. The heat should be 

 continued till the evolution of chlorine has nearly ceased, 

 which will generally be from fifteen to twenty minutes. The 

 clear fluid is now to be decanted. It is the disinfecting 

 liquor. 



This disinfecting compound may, therefore, be obtained in 

 either of the following ways : viz. 



1 . By dissolving in water the common bleaching powder, 

 usually denominated chloride of lime. 



2. By passing a stream of chlorine gas through solutions 

 of lime, soda, &c. 



3. By passing a stream of chlorine through a solution of 

 carbonate of soda, or by adding chloride of lime to dissolved 

 carbonate of soda. 



Chemical constitution. — Upon this subject there has been, 

 and still is, considerable dispute. I shall first advert briefly 

 to some opinions which have been suggested, and then offer 

 my own views. 



M. Labarraque, to whom is due the discovery of the disin- 

 fecting nature of these compounds, does not appear to have 

 understood their chemical composition, or the manner in 

 which they act upon putrid matters. He, however, calls 

 them chlorides or chlorurets of lime or soda (chlorures diox- 

 ide de calcium, and dioxide de sodium.) This name, though 

 without much propriety, they have generally retained. 



Dr. Granville, whose paper on this subject is published in 

 a late number of Brande's Journal, gives it as his opinion 

 that the solution of chloride of soda, so called, is a mixture 

 of dry chloride of sodium and neutral chlorate of soda, with 

 an excess of chlorine equal to twice the bulk of the water 

 employed in preparing the liquid according to Labarraque's 

 own formula. He infers that no such compound as chloride 

 of soda exists in this liquid, and proposes for it the simple 

 name of disinfecting liquid of soda. 



In another part of his paper Dr. Granville undertakes to 

 show that the singular properties of this liquid are owing 

 solely to the chlorine, and in no way to the agency of the 

 salts contained in it. 



