Pea Can

A cork is removed from a small can and onto the table drops a yellow pea,
a black-eye pea, a green pea and a black pea.
The spectator is asked to select one of the peas.
"Would it be magic if the only thing that comes out is the pea you selected?"
So, all of the peas are placed back into the can and sealed by the cork.
The spectator begins to say out loud as instructed "I want my pea!"
After the performer waves his or her hand over the can,
the cork is removed and out into the spectator's hand is poured warm water
(which is mistaken as pee by the spectator).