The blood pumping through the human body, and many other animals, can be thought of as a two way street with road separated by a wide distance. Blood goes out from the heart on one road and returns on another.
"Veins and arteries are like one-way streets and when a blood clot forms it can make a roadblock. In a sense, the blood behind the clot gets caught in a traffic jam."
METAMIA is a free database of analogy and metaphor. Anyone can contribute or search. The subject matter can be anything. Science is popular, but poetry is encouraged. The goal is to integrate our fluid muses with the stark literalism of a relational database. Metamia is like a girdle for your muses, a cognitive girdle.