Matarisama Doll is an ExOR
logical operating device with a one bit memory using
a water stream. The Right and Left sides of a balance
are the inputs and correspond to 1 or 0, and the outputs
are bamboo gutters connected to the inputs of the next
Matarisama doll.
A wick
delivers water to one of two reservoirs, representing
the two memory states. When water enters an input basket,
it causes the reservoir to empty into one of the outputs.
At the same time, the water pushes a bar which is connected
to the wick by strings. These strings switch the position
of the wick from one reservoir to the other.
Water from
the previous doll causes water from the reservoir to
be delivered to one of the two output gutters, depending
on the memory state represented by the position of the
wick.
The eight
dolls are arranged in a circle with each doll's outputs
connected to the doll in front of it. The process proceeds
from one doll to the next in an endless loop.