A Sail on a Yard

Carry a sail’s upper edge across the mast on a long spar. The cloth hangs below it, with a lower corner on either side of the vessel. We can change the sail’s presentation by turning the spar, then use separate lines to position those lower corners.

The spar is a yard. Its outer portions are its yardarms. In the square rig, sails hang from yards arranged across the vessel, though those yards turn substantially away from a right angle when the sail setting requires it. Square describes this transverse arrangement. The cloth may be wider than it is deep, and its sides need not form a geometrical square.

The upper edge now has a firm span, but the two corners below it are still free to move. Turning the yard changes the top of the sail’s presentation; holding the corners will need separate lines. One sail already gives the crew several different jobs.

Attach the upper edge

The square sail’s head is its upper edge, extending along the yard. On the earlier triangular sail, head identified its upper corner; this four-sided sail has an upper edge between two corners. The two side edges are its leeches; the bottom remains the foot, and the two lower corners are clews. On an oblique course, the windward side edge can act as the sail’s leading edge. The names describe parts of this supported surface without requiring the sail to keep facing directly aft.

The head must stay spread along its support. In the nineteenth-century arrangement recorded by Richard Henry Dana, a jackstay runs along the yard and receives short sail lashings. This jackstay is a rod or rope serving the spar’s sail attachment. It supplies a continuous fastening line, held to the yard at its supports. Each short lashing passes through an eyelet in the reinforced sail head and around the jackstay, transferring that portion of the sail’s pull into it and then into the yard. Dana calls these lashings robands.

At an upper corner the load is more concentrated. An earing is a short rope securing such a sail corner to its support. Here a head earing passes through the reinforced corner cringle and the yardarm’s attachment, with turns around the yard. It draws the corner out towards the yardarm and keeps the head spread. The corner patch distributes the concentrated pull into the sailcloth; the cringle receives the earing; the earing connects that corner to the spar. The jackstay and the smaller lashings carry the intervening edge.

Other attachment arrangements can use lashings directly around the yard. The jackstay provides a distinct receiving member along it. A deck safety jackstay instead receives a person’s safety tether and transfers its restraint into deck attachments. The shared name describes different objects with different loads; the yard fitting here carries the sail’s head lashings.

Raise it and keep it near the mast

First consider a yard intended to rise and descend with its sail. Its yard halyard hoists the spar. In a simple arrangement, the halyard attaches near the yard’s centre, leads upwards through a masthead block and returns to the crew. Hauling the returning part raises the attachment and yard. Securing it holds their height. The masthead block redirects the pull and passes its reaction into the mast, while the line carries the suspended load.

A heavier arrangement can add a purchase or a separate hoisting pendant between yard and tackle. Those additions change the line travel and effort through the mechanisms already encountered. They also mean that the word halyard may refer to a complete hoisting arrangement rather than one uninterrupted rope tied to the spar.

Hanging a yard from above does not by itself keep it close to the mast. The sail can pull it away, and the rolling vessel can set it swinging. A truss restrains that outward movement while permitting the required turning and tilting of the yard.

Nares’s 1877 seamanship account describes a rope truss with attachments around the yard on either side of the mast. A pendant leads through an attachment at one side, passes around the back of the mast and connects at the opposite side of the yard. Tension in this enclosing route draws the yard towards the mast. The rope, its attachments and the mast surface take the retaining load; sufficient movement in the arrangement lets the yard change its orientation. It is a restraint with particular leads and clearances, rather than a rigid binding fixing the yard at one angle.

Dana also records iron trusses for lower yards. Their moving connection carries the yard while allowing it to turn and tilt. Those lower yards were supported at a substantially fixed working height, unlike the hoistable yard in our first example. Their temporary hoisting gear put them into place; gathering a sail did not necessarily require lowering its yard. The two arrangements share the need for support and restraint but distribute those jobs differently.

The yardarms need support too. A lift, in this rigging sense, runs upwards from a yardarm towards the mast’s upper structure. Its upward pull supports that end. A lift at each side can hold the yard level; changing their effective lengths can raise one end relative to the other. An adjustable version leads through an upper block to a line or purchase that the crew can work. Where its hauling part is secured determines the working length.

With the yard hoisted, the halyard holds its height, the truss keeps its central region near the mast and the lifts support its ends and help govern its tilt. All three act on the same spar. Releasing one control can transfer load into the others, even though each governs a different movement.

Turn the yard, then place the corners

A force applied near a yardarm has a useful lever arm about the yard’s central support. A brace uses that opportunity to turn the yard horizontally. With a brace acting at each end, hauling one while allowing the other to travel turns the yard to a new angle; securing the working lines restrains further rotation.

The direction of the leads matters. In Dana’s fore-yard example, a brace runs from the crew through a block on the mast farther aft, through a block at the fore-yard or its short pendant, and back to a fixed attachment. Tension draws that yardarm towards the after lead. The other brace controls the opposite end. The after mast belongs to this particular larger vessel’s arrangement; the mechanical requirement is a useful pulling direction and a sound reaction point.

To square the yards is to brace them across the vessel, approximately at right angles to its centreline. With wind coming from astern, that setting spreads the sail across the approaching flow. To brace up is to turn a yard farther round from that square position for sailing closer to the wind. As one end moves aft and the other forward, the sail’s upper edge changes angle to the approaching air. The available angle is limited by the rig’s geometry and surrounding stays and shrouds, as well as by the useful sail setting.

The braced yard now holds the upper edge at its working angle. Below it, the lower corners still need restraint. Take the lowest square sail on Dana’s larger vessel, whose corners can be controlled from the hull. With wind coming obliquely from one side, its windward clew is drawn down and forward by a tack. This is tack in the square-sail line sense. The line leads between that reinforced corner and a forward attachment or turning block on the vessel. Its tension establishes the windward lower corner’s position.

The leeward clew is drawn aft by a sheet. In Dana’s described purchase, a block at the clew works with an after block secured to the hull. The sheet’s pull restrains that corner from flying forwards and upwards. On changing sides, the opposite corner takes the windward job. Both corners remain clews even though the active tack line has changed sides.

The tack is therefore a line in this assembly, while the tack of our earlier fore-and-aft sail was a corner. The turning manoeuvre called a tack remains another sense. What is attached, and what moves, resolves the meaning.

Braces, tack and sheet now hold the sail at its supported head and lower corners. Together they establish its orientation and tensions. Turning the yard changes the sail’s presentation without supplying every corner restraint; pulling aft at one clew cannot hold the whole upper edge at its required angle. The separate lines have to work together.

This coordination helps explain the square sail’s range. Turning the yard and controlling the corners allow useful settings away from a directly following wind. The Ma‘agan Mikhael II reconstruction, based on a wreck of about 400 BCE, demonstrated useful broad and across-wind sailing with a reconstructed square sail and paired steering blades. Its original rig had not survived complete. Its trials establish the performance of the tested reconstruction under the recorded conditions, including the effects of leeway and waves; they do not supply a universal windward angle for ancient square-rigged vessels.

Gather different parts of the sail

The working sheet and tack spread and restrain the lower corners. To take the sail out of use, the crew needs pulls in another direction. A clewline draws a clew upwards towards the yard. To clew up is to haul the clews up in this way, allowing the working corner restraints to travel as the sail gathers.

For the lowest square sails, Dana uses the more particular name clew-garnet. In his arrangement the line leads from deck through a fixed block beneath the yard, through a moving block attached to the clew, and back to a fixed attachment at the yard. Hauling the line draws the moving block and reinforced corner upwards. The supporting rope parts share the corner load, applying the purchase principle to a new moving object.

Lifting the corners leaves a considerable body of cloth between them. The bunt is the middle, bagging portion of the sail. Buntlines gather it towards the yard. In Dana’s example they lead from blocks above the sail down its forward face to attachments along the foot. Hauling them lifts those portions of the lower edge, collecting the central cloth instead of merely raising its outer corners.

Leechlines gather the side edges. They lead through blocks on the yard to attachments on the leeches, so their pull brings those edges up towards the spar. Clewline, buntline and leechline each acts on a different part of the sail. A large square sail may need all three contributions to bring its loose material within reach and keep it from hanging in a deep uncontrolled pocket.

A leech cord runs inside a sail edge and adjusts its tension to reduce flutter. These hauling leechlines run from edge attachments to blocks above and lift the edge. Their routes explain the different jobs behind the similar names.

A taut tack or sheet would hold down the corners the gathering lines are trying to raise, so those working restraints must be eased appropriately. Even then, cloth brought up by lines remains capable of catching wind. To hand a sail is to take it in and secure it; in the documented yard-sail operation, the crew follows the gathering by arranging the cloth against the yard and binding the bundle with securing lines. The hauling lines bring the sail within reach. The secured bundle keeps it contained.

The complete system for people to reach and work along high yards belongs with the larger rig.

Establish a smaller working sail

Reefing retains some useful sail area. In a conventional square-sail reef described by Dana, a reinforced band below the head is brought up to the yard. A reef earing joins a cringle at the end of that band to the yardarm. Its turns draw the new working corner out and secure it. A corresponding earing at the other end holds the band spread along the yard.

The strip between the original head and the selected reef band is gathered and secured. Below that band, the remaining cloth can be set again with its lower corners controlled. Working upper-corner loads now pass through the reef cringles and earings. The smaller ties between those corners gather the surplus strip; they do not replace the reinforced corner connections.

This differs physically from the lower-edge reef we met on the boomed mainsail. There the reduced sail acquired new lower working corners. Here the selected reef brings a new upper boundary to the yard. Both reduce exposed area through purpose-made reinforced attachments. The location of those attachments follows the support arrangement.

Use the supported yard for another load

A yard can also carry equipment unrelated to spreading its own sail. A yard tackle is a handling purchase suspended from the yard. Nares describes a pendant secured around the yardarm and connected at its lower end to an upper fiddle block. A lower block carries a hook for the load. The rope reeved between them lets the crew bring the blocks together and raise the hook.

In his worked example, yard tackles help lift a ship’s boat by its slings. The load passes from boat to sling and hook, through the lower block and rope parts to the upper block, pendant and yard. The yard’s support and restraining gear must then carry that added reaction. Other tackles control the transfer aboard. This is a prepared lifting assembly with suitable supports, not an incidental benefit available from any sail-carrying spar.

The yard halyard raises the yard itself; the yard tackle hangs a separate lifting machine from it. In the boat-lifting operation, the yard has become part of the support for a load moving beneath it.

The detailed gear in Dana’s and Nares’s nineteenth-century accounts represents mature arrangements with many specialised parts. The ancient reconstruction establishes a much earlier square-sail possibility, with substantial evidential limits between those examples. Their resemblance is no proof that every intervening craft carried the same lines.

This transverse yard can turn while the sail’s lower corners are restrained, and remain supported as the cloth is gathered or reefed. Slope the yard and move more of the sail to one side of the mast, and another handling question appears. The shape changes, but so does the path the spar and sail must take when the boat changes sides to the wind.