army bomb danger explode explosive fuse grenade military power war weapon autumn classic HDR Nyberg old river romance stream waterfall watermill brassica country field lines napus rape rural scenery seed yellow side sky spring summer background beak blue eye focus parrot rede sharp soft yellow collector energy environment lamp light pinhole renewable solar sustainable circuit clamps copper current electrical electricity ground safety stake wires access-denied access-limitations advice alert appropriate-behavior appropriate-behaviour authorise authorised authority building communicating communication denied electricity-supply exceptions limitations limited limited-entry not-allowed not-permitted power-supply prohibited prohibition regulations responsible restricted restrictions sign warning warning-sign America colorado dam Hoover Dam rock usa water brown green lion lioness nature Planckendael strength zoo