987 



Grs. Ratio. 



From 1 per cent, solution S^S 1*074? 



From 2 per cent, solution 10"21 2 



From 4 per cent, solution 19-28 3*780 



From 8 per cent, solution 33*52 6*572 



The diffusion of sulphate of alumina is very sensibly less than 

 that of sulphate of zinc at the same temperature. 



Nitrates of Silver and Soda and Chloride of Sodium, — Time of 

 diffusion seven days. 



Diffusion of nitrate of silver for seven days at 63°*4< ; two cells : — 



Grs. Ratio. 



From 2 per cent, solution 13*61 2 



From 4 per cent, solution 26*34 3*87 



From 8 per cent, solution 51*88 7*62 



Diffusion of chloride of sodium and nitrate of soda in seven days, 

 both at 63°*4 ; two cells :— 



Chloride of sodium, 2 per cent. . . 12*37 100 



Nitrate of soda, 2 per cent. 12*35 99*83 



Chloride of sodium, 4 per cent. . . 24'96 100 



Nitrate of soda, 4 per cent 23*58 94*48 



Chloride of sodium, 8 per cent. . . 48*44 100 



Nitrate of soda, 8 per cent 47*74 98*55 



As usual, the chloride is slightly more rapid in its diffusion than 

 the nitrate. 



Chlorides^ Iodides and Bromides of Potassium and Sodium. — ■ 

 Time of diffusion 5*71 days. The salt diffused was treated with 

 nitrate of silver, and the chloride of silver weighed. 



Diffusion of chloride of potassium in 5*71 days at 62° ; two cells : — 



Grs. Ratio. 



From 1 per cent, solution 6*69 1*005 



From 2 per cent, solution 13*32 2 



From 4 per cent, solution 25*94 3*895 



From 8 per cent, solution 53*64 8*054 



The ratios are in remarkably close accordance with the propor- 

 tions of salt diffused. 



The times 5*71 and seven days chosen for the chloride of potas- 

 sium and sodium, it will be observed, are as the square roots of 2 

 and 3. A certain deviation from this ratio of the times of equal 

 diffusion, appears on comparing the experimental results obtained at 

 present for these salts. 



The following is the result of the diffusion of three isomorphous 

 salts of potassium. 



Diffusion of 2 per cent, solutions in 5*716 days, at 59°'8 ; — 



Grs. Ratio. 



Chloride of potassium 12*24 100 



Bromide of potassium 12*46 101*80 



Iodide of potassium 12*51 102*21 



Mean 12*40 



The corresponding salts of sodium were also compared. 



