98 



MK. F. C. CALVERT ON THE SOLUBILITY OF 



Neither can it be admitted that the difference observed is 

 owing to the formation of a precipitate, for I have shown 

 above that the presence of a precipitate has not any influence 

 on the degree of solubility or non-formation of sulphate of 

 baryta. 



2. The increased solubility of sulphate of baryta, arising 

 from the presence of quantities of matter, can only be 

 explained by admitting that this solubility is influenced by 

 the increased quantities of salt employed, since the volume 

 of acid is the same in every case, and all other circumstances 

 are equal. 



I will again introduce the figures given above, as they show 

 in a striking manner the rapid increase of the solubility of 

 sulphate of baryta, for 1000 grs. of acid, in three successive 

 jars of the same series. 



Therefore it appears to me that we must admit that the dif- 

 ference observed is due to the quantities of matter "put 

 in presence." 



I would also, in conclusion, call attention to the enormous 

 differences between the effects of multiple volumes of an 

 acid, compared with volumes of the same acid decreasing in 

 density. 



