When the first atom was split during the early days of Manhattan project, the safety of all the people involved somehow rested on the shoulders of a professional woodsman. Specifically his axe. He was asked to swiftly cut a rope when hollered. To the other end of the rope was a cadmium strip with a lead weight attached at the bottom.
The woodsman was asked to cut the rope asap when he heard the word _____.Doing this would drop the cadmium strip in place (the core of the reactor), ready to absorb the neutrons, and putting the reactor in a safe condition.
When asked what he word meant, Fermi replied ______ ___ ____ ___ ___.
Although the methods have changed and it’s done electronically now, the term has stuck. Fill in the blanks.