490 
PROFESSOR GRAHAM ON THE DIFFUSION OF LIQUIDS. 
r925 per cent, of anhydrous hyposulphite of potash, density rOloO, diffused at 
59°‘8, in eight cells, gave 1 r66, ir67, 12‘01, 12‘26grs. ; mean 1 r90 grs. for two cells ; 
calculated for 2 per cent., 12‘37 grs. of hyposulphite of potash in two cells. 
Comparing this salt with the sulphate of the same base, we have — 
Sulphate of potash at 60°'3 . . . 11*60 100 
Hyposulphite of potash at 59°*8 . . 12*37 106*44 
A slight error in excess may possibly have been introduced from the circumstance 
that the hyposulphite of potash employed was not absolutely free from sulphate. 
Hyposulphite of Soda. — Time of diffusion 9*9 days. The diffusate was estimated in 
the same manner as the preceding salt. 
2*136 per cent, of anhydrous hyposulphite of soda, density 1*01778, diffused at .59°*9, 
in eight cells, gave 13*11, 12*775 12‘92, 11*99 grs. ; mean 12*70 grs. for two cells; 
calculated for 2 per cent., 11*89 grs. of hyposulphite of soda in two cells. 
The comparative diffusion of the salts of potash and soda appears thus : — 
Hyposulphite of potash in 8*083 days at 59°*8 . . . 12*37 100 
Hyposulphite of soda in 9*9 days at 59°*9 11*89 96*21 
The relation of the sulphate and hyposulphite of soda appears still closer. 
Sulphate of soda at 59°*6 .... 11*76 100 
Hyposulphite of soda at 59°*9 . . 11*89 101*10 
Sulphovinate of Potash. — Time of diffusion 8*083 days. The diffusate was evapo- 
rated to dryness and ignited with sulphuric acid. 
1*966 per cent, of sulphovinate of potash, of density 1*00 9 775 diffused at 59°*8, in 
eight cells, gave 12*57, 12*48, 12*12 and 12*39 grs.; mean 12*39 grs. for two cells; 
calculated for 2 per cent., 12*60 grs. of sulphovinate of potash in two cells. 
The diffusion of this salt appears in excess when compared with sulphate of potash. 
Sulphate of potash at 60°*3 . . . 11*60 100 
Sulphovinate of potash at 59°‘8 . . 12*60 108*62 
Sulphovinate of Soda. — Time of diffusion 9*9 days. The diffusate was estimated 
in the same manner as the preceding salt. 
2*063 per cent, of sulphovinate of soda, of density 1*00944, diffused at 59°*6, in eight 
cells, gave 13*32, 13*50, 13*78 and 13*15 grs.; mean 13*44 grs. for two cells; calcu- 
lated for 2 per cent., 13*03 grs. of sulphovinate of soda in two cells. 
Comparing the two sulphovinates together, we have — 
Sulphovinate of potash in 8*083 days at 59°*8 . . . 12*60 100 
Sulphovinate of soda in 9*9 days at 59°*6 ..... 13*03 103*41 
Neither of these sulphovinates appeared to suffer decomposition in the act of dif- 
fusion, at least to any considerable extent. But the experiments on both of these salts 
are less precise than usual, from the difficulty of obtaining them entirely free from 
sulphates. 
