Dr. Ure on Chloride of Lime. 19 



This powder being- well triturated with different quantities of 

 water at 60°, yielded filtered solutions of the following- densi- 

 ties at the same temperature : 



95 water + 5bleaching powder. Spec, gravity 1.0245 

 90 + 10 1.047O 



80 +20 1-0840 



The powder left on the filter, even of the second experiment, 

 contained a notable quantity of chlorine, so that the chloride 

 is but sparingly soluble in water ; nor could I ever observe 

 that partition occasioned by water, in the elements of the 

 powder, of which Mr. Dalton and M. Welter speak. Of the 

 solution 80 + 20, .500 grains, apparently corresponding to 100 

 grains of powder, gave off, by saturation with muriatic acid, 

 19 grains of chlorine, and the liquid, after evaporation and 

 ignition, afforded 41.8 grains of chloride of calcium, equi- 

 valent to 21 of lime. Here 4 per cent, of chlorine seem to 

 have remained in the undissolved calcareous powder, which, 

 indeed, on examination, yielded about that quantity. But the 

 dissolved chloride of lime consisted of 19 chlorine to 21 

 lime ; or of 4.5 at atom of the former, to almost exactly 5, 

 (which is no atomic proportion,) of the latter. The two-thirds 

 of a grain of lime, existing in lime-water, in the 500 grains of 

 solution, will make no essential alteration on the statement. 

 Now the above bleaching-powder must have contained very 

 little muriate of lime, for it was not deliquescent. Being thus 

 convinced, both by examining the pure chloride of my own 

 preparation, as well as that of commerce, that no atomic rela- 

 tions are to be observed in its constitution, for reasons already 

 assigned ; I ceased to prosecute any more researches in that 

 direction. When we are desirous of learning minutely the 

 proportion between the chloride and muriate of lime in bleach- 

 ing-powder, pure vinegar may be used as the saturating acid. 

 Having thus expelled the chlorine, we evaporate to dryness, 

 and ignite, when the acetate of lime will become carbonate, 

 which will be separated from the original muriate, by solution 

 and filtration. Or if it be feared that some muriatic acid may 

 restilt, from the action of chlorine on the hydro-carbonous base 

 C 2 



