Mancliestcr Memoirs, Vol. xlvii. (1902), No. 3. 5 



Baryta Water. 



Volume of 

 1900-1901. i Baryta Watei 

 used. 



Nov. 2 



9 

 „ 16 



Dec. 10 

 Jan. I 7 

 Mar. 1 I . 



„ 26 . 

 Apr. 15 . 



c.c. 

 10 



Bottle 



c.c. 



5-10'^ 



+ o-igr. 

 Silica. 



c.c. 



5-io=' 



+ 1 gf- 

 powd. glass. 



c.c. 

 5-10' 



These experiments, being made with alkaline solutions 

 of very different strengths, cannot be readily compared, 

 but they indicate clearly {a) that lime water in contact 

 only with the glass of the bottle loses strength much 

 more rapidly than baryta water in the same circumstances, 

 and {U) that lime water combines with silica more rapidly 

 than baryta water. Further, it was noticed on January 

 17th, after ten weeks contact, that the precipitate in the 

 lime water bottle containing powdered glass was very bulky 

 and flocculent as compared with the corresponding baryta 

 bottle. 



In the next series of experiments alkaline solutions 

 were used of practically the same strength, and the 



* Strength at starting. 



