Milk into water (100 cm. fall).
| 1 0·002 sec. |
| 2a |
| 3 0·002 sec. |
|
| 2 0·002 sec. |
|
| 4 0·009 sec. | 5 0·018 sec. |
| 6 0·018 sec. | 7 0·039 sec. |
The photographs 9, 10, and 11 (obtained after adding a little milk to the water in order to render it more visible) were at first very puzzling. What happens is that the bubble sometimes reopens very soon (or perhaps does not quite close) as in Fig. 9, and makes way for the column which rises from the base exactly as in the previous series. This column may be dimly seen through the walls of the bubble in Fig. 9, and No. 10 shows the column alone, the bubble having opened early and receded with great velocity, a few drops round the base being all that is left of it. Nos. 10a and 10b illustrate this reopening. In 10a the milk-drop was allowed to fall again into quite pure water, and the photograph shows very beautifully the summit of the column, with the original milk-drop at the top, emerging through the reopening mouth of the bubble; and Fig. 10b shows the same at a very slightly later stage when the bubble has completely retreated.
SERIES II—(continued)
| 8 0·054 sec. | 9 0·085 sec. |
| 10 0·105 sec. |
| 10a 0·103 sec. | 10b 0·111 sec. |