What is in the water?
The sand is in the water.
   src        edge_attr  dst
0    4      standing on   14
1    9   to the left of   20
2   11   to the left of   12
3   12  to the right of   16
4   12  to the right of   11
5   16   to the left of   12
6   18               in    3
7   20  to the right of    9
8   21   to the left of   22
9   22  to the right of   21