I have spent twenty-five years on boats. Now I am a docking pilot. My job is to bring in the large luxury liners and stay with them until they are safely moored in their berths. Sometimes this requires two tugs, sometimes many more, depending on the tide, the weather, and the draft of the vessel.
Most of you no doubt have seen these tugs pushing and pulling at the big liners. What they are doing doesn't seem to make much sense, but presently the big boat is alongside her pier, her hawsers made fast, and the job is done.