PROFESSOR GRAHAM ON THE DIFFUSION OF LIQUIDS. 
815 
tions in their diffusibility in alcohol, as in water, with some singular exceptions, 
such as chloride of mercury. 
1 1 . Nitrate of Baryta. 
Time of diffusion 1 T43 days*. The salt diffused was precipitated by sulphuric acid, 
and calculated from the weight of the sulphate of baryta formed. 
1. Nitrate of baryta, 1 per cent. ; density r0083. Diffused at 51°'5, in eight cells, 
6'71, 6'71, 6'84, 6'68 ; mean 6’73 grs. for two cells. 
2. Nitrate of baryta, 0*993 percent. ; density T00886. Diffused at 64°*1, in eight 
cells, 7’64, 7'70, 7‘74, 7'61 ; mean 7*67 grs. for two cells. Calculated for 1 per cent., 
7*72 grs. for two cells. 
3. Nitrate of baryta, 2 per cent ; density TO 1686. Diffused at 64°*1, in eight cells, 
15*63, 14*81, 14*41, 15*32; mean 15*04 grs. for two cells. 
4. Nitrate of baryta, 4 per cent. ; density 1*03319. Diffused at 64°*1, in four cells, 
15*36, 14*78, 14*79, 14*30; mean 14*80 grs. for one cell. 
5. Nitrate of baryta, 8 per cent ; density 1*06556, Diffused at 64°*1, in four cells, 
26*46, 26*77, 28*63, 27*13 ; mean 27*25 grs. for one cell. 
The diffusion from the 1 per cent, solution increases by a rise of temperature from 
51°*5 to 64°*1, from 6*73 grs. to 7*72, or from 100 to 114*7, which is an increase of 
1*17 per cent for 1°. 
Diffusion of Nitrate of Baryta in 1 1*43 days at 64°*1 ; two cells. 
From 1 per cent, solution . 
Grs. 
. . 772 
Ratio. 
1*0*26 
From 2 per cent, solution . 
. . 15*04 
2 
From 4 per cent, solution . 
. . 29*60 
3*936 
From 8 per cent, solution . 
. . 54*50 
7*247 
12. Nitrate of Stronti a. 
Time of diffusion 11*43 days. Of anhydrous nitrate of strontia 0*82 percent.; 
density 1*0063, Diffused at5T*5, in eight cells, 5*59, 5*62, 5*44,5*69 ; mean 5*59 grs. 
for two cells ; calculated for 1 per cent,, 6*79 grs. at 51°*5 for two cells. 
The diffusion of nitrate of strontia almost coincides with that of the isomorphous 
nitrate of baryta at the same temperature. 
Diffusion from 1 per cent, solutions at 51°*5 in 11*43 days. 
Nitrate of baryta 6*73 100 
Nitrate of strontia 6*79 100*89 
* This time is to that of sulphate of magnesia (16' 166 days) as the square root of 8 is to the square of 16 : 
but does not appear to express the true relation between these salts. 
