PROFESSOR GRAHAM ON THE DIFFUSION OF LIQUIDS. 
17 
3‘12 grs. of carbonate of soda. The salts actually diffused out were therefore in the 
proportion of — 
Carbonate of soda 36’37 
Carbonate of potash 63'63 
100*00 
(2.) In another similar experiment from a six-ounce phial into 8|- ounees of water, 
the liquid of the water-jar, after twenty-five days’ diffusion, contained the two carbo- 
nates in nearly the same proportions as before, namely — 
Carbonate of soda 35*2 
Carbonate of potash 64*8 
1000 
(3.) A partial separation of the salts of sea-water was effected in a similar manner. 
The sea-water (from Brighton) was of density T0265. One thousand grs. of the 
liquid yielded 35*50 grs. of dry salts, of which 2*165 grs. were magnesia. The dry 
salts contain therefore 6*10 per cent, of that earth. 
Six thousand-grain phials, of T1 inch aperture, were properly filled with the sea- 
water and placed in six tumblers, each of the last containing 6 ounces of water. 
Temperature about 50°. The diffusion was interrupted after eight days. The salts 
of the sea-water were now found to be divided as follows : — 
Diffused into the tumblers .... 92*9 grs., or 36*57 per cent. 
Remaining in the phials 161*1 grs., or 63*43 per cent. 
254*0 100*00 
Rather more than one-third of the salts has therefore been transferred from the 
solution phials to the water-jars by diffusion. 
Of the diffused salts in the tumblers, 46*5 grs. were found to contain 1*90 gr. mag- 
nesia, or 4*09 per cent. Hence we have the following result : — 
Magnesia originally in salts of sea-water . . . 6*01 per cent. 
Magnesia in salts diffused from sea-water . . . 4*09 per cent. 
The magnesia, also, must in consequence be relatively concentrated in the liquid 
remaining behind in the diffusion cells. 
A probable explanation may be drawn from the last results of the remarkable dis- 
cordance in the analysis of the waters of the Dead Sea, made by different chemists 
of eminenee. I refer to the relative proportion of the salts, and not their absolute 
quantity, the last neeessarily varying with the state of dilution of the saline water 
when taken up. The lake in question falls in level 10 or 12 feet every year, by eva- 
poration. A sheet of fresh water of that depth is thrown over the lake in the wet 
season, which water may be supposed to flow over a fluid nearly 1*2 in density, 
without greatly disturbing it. The salts rise from below into the superior stratum 
MDCCCL. D 
