only be done in a dire emergency; where speed of manoeuvre outweighed the enormous risk of being caught in irons. By far the most common way of working to windward was wearing round (gybing). In addition, sailing with the wind directly aft ("abaft") or directly on either side ("abeam") was difficult and inefficient. Sails with the wind in those directions do not fill. The wind must be allowed only from the quarters. At those angles the sails fill and there is a component of force in the desired direction. If the wind is directly abeam, the ship must fall off or close up. The ship may sail on either side of a wind directly astern. A manoeuvre similar to coming about is used to move the wind from one side to another: wearing. The helm is put over, the sails go limp, they are adjusted to fill on the other side. The ship does not have to rotate as far, so the manoeuvre is less disruptive. Wind is everything to a sailing vessel. It cannot move anywhere without it (is "becalmed"). If the wind is too great the sails may have to be shortened to present less area, a procedure call "reefing." In a storm the ship must sail close to the wind or have it close astern. As the waves are generally coming in with the wind, a ship sailing close into the wind generally cuts them perpendicularly and only pitches; i.e., drops into the troughs and rises on the crests. A ship with the storm wind abeam is struck longitudinally and rolls treacherously, running a risk of capsizing. To avoid that risk the captain must run before the wind. All directions are evaluated with regard to the wind. The side of a ship toward the wind is called the "weather" or "upwind" side; away, the "lee" or "downwind" side (refer to Windward and leeward). Much has been made of the tactics of various great sailing captains, but the greatest constraints come from wind direction and relative position. The captain of a steam vessel has considerably more freedom to take his ship where he wishes to take it, but the tactics of a sailing captain are to a large extent already predetermined by nature. To get to any point the sailing captain must plot a course taking wind direction into consideration. He must have judgement and skill, and is