8 Dr. Ure on Chloride of himc. 



Now, surely Mr. Dalton's own atoms should agree together, 

 or the constitution of what he reckons a suboxymuriate should 

 be a definite proportion. Yet his first and second oxymuriates 

 (exclusive of muriate and water) seem sufficiently discordant ; 

 for 23.2 : 38.4 : : 14.5 : 24, and not 30, as he has given it. 

 Dr. Thomson has accommodated his numbers to suit the ato- 

 mic theory, and has thrown off", for that purpose, the suitable 

 quantity of " uncombined lime." The great error, in my appre- 

 hension, attending all these statements, is occasioned by the 

 ultra-atomical notions of the authors. They offer no evidence 

 whatever, that when chlorine is presented to pulverulent slaked 

 lime, 22.23 parts of this alkaline base do attach themselves to 

 14.29 parts of chlorine, to form 36.52 of a subbichloride, 

 while there remains in the mixture 28.05 of lime, equally 

 greedy of chlorine, and yet altogether deprived, by their com- 

 panion particles, of that energetic element. Dr. Thomson's 

 last statement above is built on this foundation. I believe, on 

 the contrary, and hope to make it appear presently, that all the 

 particles of hydrate of lime attach to themselves a quantity of 

 chlorine, relative to the proportion and pressure of the gas, up 

 to their saturating limit, which seems to be one atom of chlo- 

 rine for one of tri-hydrate of lime, and that there is, therefore, 

 no mixture of an atomic subbichloride, and of free lime, in the 

 powder. 



But before relating my own experiments, I must advert for a 

 moment to M. Grouvelle's " Researches on the Combinations of 

 Oxides with Chlorine, Iodine and Cyanogen," inserted in the An- 

 nates de Chijnie et de Physique, for^May 1821. This gentlemen 

 asserts, that M. Welter is the first, to his knowledge, who oc- 

 cupied himself with the analysis of chloride of lime. But we 

 have shewn above, that M. Welter's researches are five years 

 posterior to those of Mr. Dalton, who had also anticipated all 

 the atomical inductions of the French chemists. M. Grouvelle's 

 mode of examining the chloride of lime, seems to me singu- 



» Junah of Phil. I, p. ly. 



