box in

For running along the public roads the wheels and motion are completely boxed in; ….

Realizing he is now boxed in on all sides, Hipper decides the only remaining card he has to play is to sell his ships as dearly as possible. The remaining German ships make a hard turn southeast, and drive headlong at the Grand Fleet. It is a brave gesture, but only eight of the ships emerge from the pall of smoke that roughly marks the original German line of advance. Two more emerge minutes later, but that is all.