ON THE THICKNESS AND SURFACE TENSION OF LIQUID FILMS. 
675 
Experiment XVII. 
Two measurements were made, when the sphere was colourless, and the cylinder 
also, with the exception of about 2 mm. at the top, which showed rings of colour. 
t 
8 
Mean. 
m. 
5 
8 
20-67 
20-69 
20-68 
The films were then separated, and the sphere was flooded. At 40 m the stop-cock 
was again opened, and the following readings, beginning at 44 m , gave 
8=20-58, 20-69, 2071, 20'66, 20’66. 
The last two readings were as follows :— 
t 
a 
a 
8 
Mean. 
m. 
58*5 
{2b, T (2, 0)} 
{176, Y (1, 5), R (1, 5)} 
20-76 
20-77 
60-0 
{2-56, G- (2, 5)} 
{186, Y (1, 5)} 
20-79 
cZT/T = 0-009/3-7x0-76 = 0-3'2 per cent. 
Experiment X VIII. 
Three measurements were made when the films were colourless, or very nearly so. 
t 
d 
Mean. 
m. 
7 
20-69 
10 
20-88 
20-78 
12 
20-78 
The following readings gave S = 20'61, 20‘85, 2076, 20"80, 20*71, 20"84, 20"96, 
20-75, 20-97. 
The last two observations were as follows :— 
t 
c. 
C c 
& 
Mean. 
h. m. 
1 11 
{0-756, G (4, 5)} 
{186, G (2, 5)} 
2T12 
2L15 
1 18 
{0-756, BR (3, 8)} 
{226, W (1, 5)} 
21-18 
7T/T = 0-037/3'7x 0-87 = 1-15 per cent. 
4 r 2 
