The Davies' Block is a sequential interchange block
on Bow Road, played with a black token
. This blocks all movements West through Bow Road, but not all movements East. The token cannot be shunted
or switched until an equivalent number of black tokens have been removed from anywhere on the board excluding Bow Road. This often causes an uncomfortable situation, as the usual way to do this is to sacrifice valuable tokens they have built up for a rebound on the Northern line.
Traditionally, the black token should be as dishevelled as possible, and, if space permits, be placed skew on the Bow Road marker.