56 Jones — Action of Carbon Dioxide on the Borates^ etc. 



they show anything — make it clear that even these salts can- 

 not be weighed with safety. 



These experhnents leave nothing more to be done to prove 

 the impossibility of bringing to definite and constant weights 

 the mixtures resulting from the method described by Morse 

 and Burton. Furthermore, in the promised forthcoming con- 

 tinuation of this study by Morse and Horn, I see no possibility 

 of any other deduction. 



In conclusion, then, I reiterate : — First. Carbon dioxide 

 decomposes the metaborate of barium in either aqueous or 

 alcoholic solutions. 



Second. The boric acid liberated may in part escape during 

 evaporation to dryness and especially before reaching that 

 temperature at which it has completely recombined with the 

 barium, replacing carbon dioxide. 



Third. A mixture, containing barium carbonate and hydrated 

 boric acid, or barium carbonate with the hydrated metaborate 

 and boric acid, or even barium carbonate and hydrated metabo- 

 rate, cannot with safety be brought to definite composition for 

 weighing. 



