<N/4> Chain and Circulate In
This is closely related to Spin Chain and Circulate In. In fact,
3/4 Chain and Circulate In is the same as Fan Chain and Circulate In.
Ends: Circulate and then Cross Over Circulate.
Centers: Cast the indicated fraction, which should leave them in a line.
The center 2 then trade, then cast off 3/4 (always), and Spread to let
the others come into the center on their Cross Over Circulate.
The starting setup is typically lines if the fraction is odd,
and diamonds if it is even.
The two groups of people should finish at about the same time, so ideally
things should go smoothly. But just in case, it is wise for then ends
to think in terms of two circulates, figure out who is going to be spreading
outward, and then spread inward in a way that neither knocks them down nor
confuses them.
When done from T-bones, the same considerations apply as for Change Lanes.
Because dancers often start doing a trade as soon as they hear "Spin Chain",
and because this sounds similar, an extremely common mistake is to start
this with a trade. Good dancers go out of their way to be careful about
this. The sound effect is "It starts in the center".