AT THE BOUNDARY OF A LIQUID IN MOTION. 
5C9 
At slightly different pressures— 
Pressui'e. 
Temperature. 
Time. 
mm. 
O 
12 29-7 
Silvered . 
406-4 
12-52 
JJnsilvered . 
406 5 
12-62 
12 24-3 
JJnsilvered, corrected for temperature and change in ... 
12 26-4 1 
Silvered, observed time 
12 29-7 / 
Tube No. 3. —{r = "OoG cm. ; I = 19’98 cms.) 
Total pressure at beginning of each observation 84‘15 cms. of water + 21’028 cms. 
of mercury ; equivalent to 368'62 cms. of water. The critical pressure forthis tube is 
440 cms. of water. The tube was silvered with solutions of half strength very 
carefully. 
Mean reading 
of katheto meter. 
Temperature. 
Time. 
Silvered . 
22-963 
1270 
15 
46-5 
22-956 
12-93 
15 
23-0 
22-95 5 
13-41 
15 
18-0 
22-966 
12-76 
15 
34-0 
22-960 
12-95 
15 
30-4 
JJnsilvered . 
22-959 
13-04 
15 
I 6-5 
23-0o4 
13-69 
15 
7-3 
22-982 
13-37 
15 
11-9 ' 
Silvered, corrected for change 
in radius — 016 per cent., for 
15 
21-5 . 
temperature — 0 93 per cent., and for pressure + 0'14 per cent. 
In this very small tube there is thus a choking effect which increases the time by 
about 1 per cent. 
The same tube was then re-coated with a very thin deposit which was just trans¬ 
parent to blue light. 
Pressure. 
Temperature. 
Time. 
mm. 
0 
/ // 
23-026 
15-31 
14 48-2 
23-037 
15-27 
14 50-8 
23-032 
15-29 
14 49-5 
MDCCCXC. — A. 
4 D 
