In 19 11, a young physician named francis peyton rouse set up a cancer research laboratory in new york at what is now rockefeller university. He removed the tumor of a dying chicken and mixed it with saline solution to inject into healthy chickens. The healthy chickens develope the same tumors. Rous concluded had to be caused by a virus. Years later, this same problem, whether cancer could spread like a virus, came to obsess ludvic gross. Sometimes mice came down with lucamia murine lucamia, which is a lot like human lucamia. Gross bred mice to show how the disease was communicated from one generation to the next. But the same thing happened