N.C., a white male infant, born June 18, 1958, was admitted to hospital on May 18, 1959, when 11 months old, with a five days' history of being irritable and apparently suffering from severe colicky abdominal pain for the previous 24 hours. On the day of admission his bowels had not moved and he vomited several times. He looked pale and ill and a mass could be felt in the right hypochondrium. T...