Marble AND gate description

We can use the language defined in the previous post to describe a marble AND gate. Where i1 and i2 are the inputs, o1 is the output, and X is dumped into a marble recycling bin.

i1     i2   Two marbles are dropped into two channels, maybe not at the same time.
    Y        The two channels narrow into one.
   12       A switch sends the first marble to the left
    -|        Where it is stopped until the second marble comes through
    Y       Now the marbles are nearly time synchronized and narrow into a single channel
   //\        Where they are separated big from small
  Z  |       Any big marbles are delayed, ensuring that if there is a small marble, it goes first
   Y        Then back into a single channel
   12       The first marble goes to the left output and the second one is dumped
o1   X

So this device waits until both inputs have come in and then slows down any big marbles, ensuring that if there is a small marble it will be output and the other marble will be dumped. If both inputs are big marbles than one of them will arbitrarily end up as output while the other is dumped.

This gives us the proper truth table:
i1  i2  o1
o   o   o
o   O  o
O  o   o
O  O  O

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