Read this excerpt from "A Drop in the Bucket."

In one of the Smithsonian’s curation rooms, she carefully places "Diane France's brain" on a table and props it up around the edges with clay. But the clay doesn't stick to the table, and the brain loses its shape. That's no good.


Next, she tries putting the brain in a pan and smooshes clay around the inside edge of the container. Still no good.


Finally, after more trial and error, Diane grabs a stainless steel bowl—just like the one in her kitchen—and presses clay in a ring around the curved bottom. She adds a layer of formalin-soaked paper towels to keep the bottom of the brain damp. Then, she carefully nestles the brain in the ring. It works! The brain holds its shape as she coats the top with a liquid form of silicone rubber. The rubber hardens to make one-half of a mold.

Which detail from the excerpt identifies a problem?