PROFESSOR GRAHAM ON THE DIFFUSION OF LIQUIDS. 
817 
15. Acetate of Baryta. 
Diffused for 16’ 166 days. The solution contained 0‘977 per cent, of anhydrous 
salt, with the density TOO/S. The same addition of acetic acid was made to it as to 
the preceding acetate of lead, in order that the circumstances of diffusion might be 
similar for both salts. The salt diffused was estimated also in the form of sulphate, 
Diffused at 53°‘5, in eight cells, 7'30, 7’38, 7’40 and 7'21 grs. in two cells; mean 
7’33 ; or 7*50 for 1 per cent, in two cells. 
Diffusion of 1 per cent, solutions in 16‘166 days; two cells. 
Acetate of baryta at 53°‘5 .... 7'30 100 
Acetate of lead at 53°T 7'84 104’53 
Here, of two isomorphous salts, that of greatest atomic weight sensibly exceeds the 
other in diffusibility. 
16. Chloride of Barium. 
Time of diffusion 1T43 days. The diffused salt was weighed as sulphate of 
baryta. 
1. Chloride of barium, 0‘99 per cent. Diffused at 50°’9, in eight cells, 7'91, 7'27i. 
7'42, 7‘12 ; mean 7*43 grs. of chloride of barium for two cells; calculated for 1 per 
cent., 7'50 grs. at 50°'9 for two cells. 
The diffusion of this salt being manifestly more rapid than that of the chloride of 
calcium, a shorter time was tried, which is to seven days, the time of chloride of so- 
dium, as the square root of 3 to the square root of 4’5. Time of diffusion 8‘57 days. 
2. Chloride of barium, TOl per cent.; density T0095. Diffused at 63°, in eight 
cells, 6*46, 6‘44, 6'41, 6‘27 ; mean 6'39grs. for two cells; calculated for 1 per cent., 
6*32 grs. at 63° for two cells. 
3. Chloride of barium, 2‘02 per cent.; density 1*0183. Diffused at 63°, in eight 
cells, 11*98, 12*03, 12*75, 12*03; mean 12*20 grs. for two cells; calculated for 2 per 
cent., 12*07 grs. at 63° for two cells. 
4. Chloride of barium, 4*04 per cent.; density 1*0359. Diffused at 63°, in four 
cells, 12*43, 12*30, 11*87, 11*86; mean 12*10 grs. for one cell; calculated for 4 per 
cent., 11*98 grs. at 63° for one cell. 
5. Chloride of barium, 8*08 per cent.; density 1*0712. Diffused at 63°, in four 
cells, 23*17, 23*05, 22*98, 23*62 ; mean 23*20 grs. for one cell; calculated for 8 per 
cent., 22*96 grs. at 63° for one cell. 
Diffusion of Chloride of Barium in 8*57 days at 63° ; two cells. 
Grs. 
Ratio. 
From 1 per cent, solution . . 
6*32 
1*047 
From 2 per cent, solution . . 
. 12*07 
2 
From 4 per cent, solution . . 
. 23*96 
3*970 
From 8 per cent, solution . . 
. 45*92 
7-608 
5 M 
MDCCCL. 
