PROFESSOR GRAHAM ON THE DIFFUSION OF LIQUIDS. 
819 
about 3| pel’ cent, in the diffusion of these two isomorphous salts, the chloride of 
barium, which possesses the highest atomic weight, having the advantage. 
The diffusion of the 1 per cent, solution of the same salts for the longer period of 
1 r43 days, gives 7‘50 for chloride of barium at 50°’9, and 7°'52 for chloride of stron- 
tium at 51°, or nearly the same temperature. For the first time we have in the barytic 
salts a divergence between chlorides and nitrates, for the nitrates of the same bases 
have a number about 6’8 only at the same temperature. I am led however to believe 
that this discrepancy becomes much less at low temperatures by experiments which 
are at present in progress. 
18. Chloride of Calcium. 
Time of diffusion 11’43 days. The salt diffused was weighed as sulphate of lime. 
1. Chloride of calcium, T065 per cent. ; density T0091. Diffused at 50°’9, in eight 
cells, 6’95, 7‘09, 6’78, 6’94 ; mean 6’94 grs. of chloride of calcium for two cells; 
calculated for 1 per cent., 6’51 grs. at 50°’9 for two cells. 
2. Chloride of calcium, T03 per cent. ; density r0089. Diffused at 63°’8, in eight 
cells, 8’08, 8’ 13, 8’28, 8’19 ; mean 8T7 grs. for two cells ; calculated for 1 per cent., 
7*92 grs. at 63°’8 for two cells. 
3. Chloride of calcium, 2-06 per cent. ; density T0171. Diffused at 63°’8, in eight 
cells, 15’70, 15’33, 16’48, 15*82; mean 15*83 grs. for two cells; calculated for 2 per 
cent., 15*35 grs. at 63°*8 for two cells. 
4. Chloride of calcium, 4*12 per cent.; density 1*0334. Diffused at 63°*8, in four 
cells, 15*24, 16*20, 15*89, 16*20; mean 15*88 grs. for one cell; calculated for 4 per 
cent., 15*39 grs. at 63°*8 for one cell. 
5. Chloride of calcium, 8*23 per cent.; density 1*0652. Diffused at 63°*8, in four 
cells, 32*97, 31*17, 30*64, 31*90; mean 31*67 grs. for one cell; calculated for 8 per 
cent., 30*78 grs. at 62°*8 for one cell. 
The diffusion of the 1 per cent, solution of chloride of calcium is increased by a 
rise of temperature from 50°*9 to63°*8, from 6*51 to 7‘92, or from 100 to 121*6, which 
is an increase of 1*674 per cent, for 1°. 
Diffusion of Chloride of Calcium in 1T43 days at 63°*8 ; two cells. 
Grs. 
Ratio. 
From 1 per cent, solution . 
. . 7-92 
1*032 
From 2 per cent, solution . 
. . 15*35 
2 
From 4 per cent, solution . 
. . 30*78 
4*010 
From 8 per cent, solution . 
. . 61*56 
8*021 
We may now observe how far the diffusion of the chloride of calcium is analogous 
to that of nitrate of lime. At the inferior temperatures, the results for the 1 per cent, 
solution of these two salts were as follows : — 
Chloride of calcium at 50°*9 ... 6*51 100 
Nitrate of lime at 51°*5 6*54 100*46 
5 M 2 
