Manchester Memoirs, Vol. xlvii. (1902), No. 3. 



glass. In the case of the bar3^ta water, the strength in 

 the glass bottle remained still more constant, and was 

 absolutely the same at the end of eleven months, while 

 the action on silica was less than with either of the other 

 alkalies, and in the case of the powdered glass, the 

 strength had only fallen O'l of a cubic centimetre. 



The third series of experiments was an exact repetition 

 of the second, and confirms the results in every respect. In 

 some cases it will be noticed that the strength of the 

 alkaline liquid in contact with powdered glass is increased 

 at the beginning of the experiment. This is no doubt 

 due to the fact that powdered glass has an alkaline 

 reaction. It can be detected with reddened litmus, but is 

 much more readily shown by the exceedingly sensitive 

 reagent phenol-phthalein. 



Table C. Third Serie.s. 

 Lime Water. 



^'olLlme of 



Limt- Water 



used. 



c.c. 

 10 



Bottle. 



c.c. 



945' 



9'45 

 9'35 

 9 '3° 

 915 

 9 "05 

 8 90 

 8-8o 



+ 1 gi'- 



Silica. 



+ I g'- 

 powd. glass. 



c.c. 

 9"45* 



6 30 

 57>5 

 075 

 o"6o 

 o'6o 

 o"6o 

 060 



c.c. 

 9-45^ 



9 35 



9"30 



930 

 8-50 



4'20 



3-80 

 3-55 



* Strength at starting. 



