8 
PROFESSOR GRAHAM ON THE DIFFUSION OF LIQUIDS. 
Diffused in 1st two days 3’95 grs. 
Diffused in 2nd two days 3‘00 grs. 
Diffused in 3rd two days 2‘91 grs. 
Diffused in 4th two days 3‘26 grs. 
The diffusion appears to proceed pretty uniformly, if the amount diffused in the 
first period of two days be excepted. Each of the phials contained at first about 
108 grs. of salt, of which the maximum quantity diffused is 13T2 grs. in eight days, 
or of the whole salt. Still the diffusion must necessarily follow a diminishing 
progression, which would be brought out by continuing the process for longer time, 
and appear at the earliest period in the salt of most rapid diffusion. 
All the experiments which follow being made like the preceding on comparatively 
large volumes of solution in the phial, and for equally short periods of seven or eight 
days, may be looked upon as exhibiting pretty accurately the initial diffusion of such 
solutions, the influence of the diminishing progression being still small. The volume 
of water in the water-jai- is also relatively so large, that the experiment approaches 
to the condition of diffusion into an Unlimited Atmosphere. 
2. Diffusion of various Salts and other Substances. 
With these notions regarding the influence of temperature and proportion of salt 
on the amount of diffusion, an examination was next undertaken of the relative dif- 
fusibility of a variety of salts and other substances. The results of this first survey 
I shall state as shortly as possible, as I consider these, as well as the experiments 
which preceded, as of a preliminary character. The experiments were all made by 
means of the diffusion phials already described, namely, the six-ounce phials, and 
with similar manipulations. 
In the following experiments, the diffusion took place at a temperature ranging 
from 62° to 59°, mean 60°‘5, and was continued for a period of eight days ; the 
proportion of salt in solution to be diffused being always 20 salt to 100 water, or 
1 to 5. I add as usual the density of the solutions. 
Table II. — Diffusion of solutions of 20 salt to 100 water, at 60°’5, for eight days. 
Name of salt. 
Density of 
solution at 60°. 
Anhydrous' salt diffused. 
In grains. 
Means. 
Chloride of sodium 
1-1265 
58-5 
Chloride of sodium 
1-1265 
58-87 
58-68 
Sulphate of magnesia 
1-185 
27-42 
27-42 
Nitrate of soda 
1-120 
52-1 
Nitrate of soda 
1-120 
51-02 
51-56 
Sulphate of water 
1-108 
68-79 
Sulphate of water 
1-108 
69-86 
69-32 
Crystallized cane-sugar 
1-070 
26-74 
26-74 
Fused cane-sugar 
1-066 
26-21 
26-21 
Starch-sugar (glucose) 
1-061 
26-94 
26-94 
Treacle of cane-sugar 
1-069 
32-55 
32-55 
Gum-arabic 
1-060 
13-24 
13-24 
Albumen 
1-053 
3-08 
3-08 
