What is common to the carriage and the clock?
The color, both the carriage and the clock are white.
   src        edge_attr  dst
0    0   to the left of   13
1    1   to the left of    5
2    1   to the left of   15
3    5  to the right of    1
4    5               on    8
5    5  to the right of   10
6   10   to the left of    5
7   13  to the right of    0
8   15  to the right of    1