> Using just a centrifuge, water, detergent, and acid, he purified nucleic acid from his smooth strep culture. Precipitated with alcohol, it became fibrous. He

> Using just a centrifuge, water, detergent, and acid, he purified nucleic acid from his smooth strep culture. Precipitated with alcohol, it became fibrous. He added a tiny bit of it to the rough culture, and lo, that culture became smooth in the following generations. This fibrous stuff, then, was “the transforming principle”—the long-sought agent of heredity. I guess that’s why we still call the process of bacteria taking up DNA “bacterial transformation”. It was the terminology they used early on.