"I imagine," said the lieutenant, gravely, "that their activities will broaden out as they get warmed up to their work.  Understand? What I mean is this: You boys are risking your lives in undertaking this mission.  You will be followed and spied upon from the minute you leave San Francisco, and the chances will be all against you when you reach your field of operations.  Even the Government cannot protect you in your undertaking, for the Government is not supposed to know anything about this case."