378 Mr. R. Pliillips on the Chlorides of Lime and Soda. 



the uncombined chlorine gas which the water holds in solu- 

 tion. Now admitting for a moment this to be the case, and 

 that no such compound as chloride of soda exists, the same 

 explanation cannot apply to the action of chloride of lime : and 

 it is singular that Dr. Granville has taken no notice of this 

 substance, although according to M. Labarraque it is gene- 

 rally employed for disinfecting apartments, while the chloride 

 of soda " is especially employed in topical and extei-nal ap- 

 plications to wounds and ulcers affected with hospital gan- 

 grenes, &c." (Alcock on the Use of the Chlorurets, p. 126.) 



Some late experiments have proved in a most decided man- 

 ner that the explanation which Dr. Granville has offered, is 

 not a correct view of what actually occurs. M. Gaultier de 

 Claubry has shown, that air which was passed through putrid 

 blood and afterwards into a solution of chloride of lime, was 

 rendered inodorous, and was completely purified, occasioning 

 the precipitates of carbonate of lime ; but in a similar experi- 

 ment the foetid air was passed through a saturated solution of 

 caustic potash ; the chloride of lime had then no effect upon 

 it, and it retained its insupportable odour : this is decisive as 

 to the action of the carbonic acid of foul air in evolving the 

 chlorine by which it is purified. 



I have already mentioned that chloride of soda does not 

 even by ebullition lose its bleaching property; and this is an- 

 other proof that its action does not depend upon the mere gas 

 which it holds in solution; for it will hardly be maintained that 

 any circumstance less than combination will retain chlorine in 

 water at a boiling temperature. It also retains its power to a 

 considerable extent even after evaporation to dryi'iess. 



Dr. Granville states, that the salt in question is a mixture 

 of 73-53 of chloride of sodium and 28*47 of chlorate of soda; 

 I am quite at a loss to conjecture how Dr. Granville obtained 

 this result, either by calculation or experiment. For prepa- 

 ring the chloride of soda M. Labai'raque directs that a solution 

 of 288 parts of crystallized carbonate of soda, is to have the 

 chlorine evolved fi'om the decomposition of 66 parts of com- 

 mon salt passed into it. 



Now as 288 are equivalent to 2 atoms of crystallized carbo- 

 nate of soda, there will be required the chlorine of 2 atoms = 

 120 of common salt to convert them into chloride of sodium 

 and chlorate of soda ; and even admitting, what I believe is 

 not the case, that the chlorine of the 66 parts of the common 

 salt, converts, as far as it goes, the carbonate of soda into 

 chlorate of soda and chloride of sodium, the quantity is so de- 

 ficient that the dry salt must consist very nearly of 

 Chloride of sodium . . 45 

 Chlorate of soda ... 16 

 Carbonate of soda . . 39 



Too LXXV. No- 



