202 
solutions were prepared by dissolving each of the following number of 
grams of salt in 200 ce. of distilled water: 7.82 g., 15.64 g., 31.28 g., 46.92_¢., 
62.56 g., 
72 g. (saturated solution). 
Six solutions each of cepper sulphate and sugar were prepared in the 
same way as in the case of sodium chloride, and each solution was tested 
for the number of grams to separate the liquid films. 
The results for the eighteen different solutions are tabulated as fol- 
lows: 
First.—The number of grams to separate the disk from the solutions 
when 7.82 ¢. of each of the three materials were dissolved in 200 cc. of 
water. 
Trial Sodium 
vase: Chloride. 
1 42.45 
2 42.50 
3 42 .50 
Mean. 42.48 
Copper 
Sulphate. 
Sugar. 
Second.—The number of grams to separate the disk from the solution 
when 15.64 g. of each of the three materials were dissolved in 200 ce. of 
water. 
A Sodium Copper . 
é Sugar. 
Trial. Chloride. Sulphate. ara 
l 42.15 49.20 50.50 
2 42 .00 49.30 50.52 
3 41.95 19.35 50.51 
Mean. 42.03 49 .28 50.51 
Third.—The number of grams to separate the disk from the solutions 
when 31.28 g. of each of the three materials were dissolved in 200 ce. of 
water. 
7 Sodium Copper 
Trial. Chloride. | Sulphate. 
| 
1 46 .39 | 50.35 
2 46.30 | 50.37 
See eee | 50.35 
Mean 46.345 50.356 
Sugar. 
