Spritsail
Encyclopedia
The spritsail is a form of three or four-sided, fore-aft sail and its rig
Rig
Rig may refer to:* Rig, Something that a dog pulls when Mushing* Rig, a slang term referring to a tractor unit* Drilling rig, a structure housing equipment used to drill or extract oil from underground* Gaming rig, a PC built for high-performance gaming...

. Unlike the gaff
Gaff rig
Gaff rig is a sailing rig in which the sail is four-cornered, fore-and-aft rigged, controlled at its peak and, usually, its entire head by a spar called the gaff...

 where the head hangs from a spar along its edge, this rig supports the leech of the sail by means of a spar or spars named a sprit. The forward end of the sprit spar is attached to the mast
Mast (sailing)
The mast of a sailing vessel is a tall, vertical, or near vertical, spar, or arrangement of spars, which supports the sails. Large ships have several masts, with the size and configuration depending on the style of ship...

 but bisects the face of the sail, with the after end of the sprit spar attaching to the peak and/or the clew of the sail. It is said to be the ancestor from which the common gaff rig evolved in 16th-century Holland. Historically, spritsails were the first fore-and-aft rig
Fore-and-aft rig
A fore-and-aft rig is a sailing rig consisting mainly of sails that are set along the line of the keel rather than perpendicular to it. Such sails are described as fore-and-aft rigged....

s, appearing in Greco-Roman navigation in the 2nd century BC.

Barges

The spritsail was best known from its use in the Thames sailing barge
Thames sailing barge
A Thames sailing barge was a type of commercial sailing boat common on the River Thames in London in the 19th century. The flat-bottomed barges were perfectly adapted to the Thames Estuary, with its shallow waters and narrow rivers....

, which employs two similarly sized spars to form the framework for the sail area. In a barge, the mast is stepped vertically in a tabernacle
Tabernacle (disambiguation)
The Tabernacle most commonly refers to the Jewish Tabernacle , which was a movable tent and worship facility used by the Israelites for the worship of Yahweh as recorded in the Book of Exodus...

, whilst the sprit is suspended from the mast at an angle of about 30° from vertical, near the mast's foot, with the foot of the sprit to the starboard side of the mast, in a kind of basket, called a muzzle. The sprit is free to move laterally, nearly as far to each side as the shrouds. This enables the vessel to reach and run. The instability caused by allowing such a weighty spar to extend too far away from the vessel's centreline, however, had to be borne in mind when designing hull and rigging. The peak of the sail is permanently attached to the head of the sprit.
The spritsail rig was normally used without a boom
Boom (sailing)
In sailing, a boom is a spar , along the foot of a fore and aft rigged sail, that greatly improves control of the angle and shape of the sail. The primary action of the boom is to keep the foot of the sail flatter when the sail angle is away from the centerline of the boat. The boom also serves...

. (The latter was usually found on fore-and-aft rigged vessels to keep the mainsail in an aerodynamically efficient shape.) Such loose-footed sails can also be found on the Norfolk wherry
Norfolk wherry
The Norfolk wherry is a type of boat on The Broads in Norfolk, England. Three main types were developed over its life, all featuring the distinctive gaff rig with a single, high-peaked sail and the mast stepped well forward.-Development of the wherry:...

 and the bawley
Bawley
A Bawley was an English sailing vessel typified by a boomless cutter rig and probably named for having a boiler for cooking shrimp in amidships....

 class of vessels and was a feature of the Cromster
Cromster
The Crommesteven or cromsteven, often as crompster, cromster or crumster was a type of small warship used by the Dutch Republic and later by the British fleets during the sixteenth and seventeenth centuries...

. In this last example, the ability to furl the foot of the sail cleared the deck of the sheet while the sail could still be controlled by the vangs. This made gunnery much more readily possible.

In the more usual, commercial vessel, the rig has the advantage of freeing the cargo hatch of obstructions such as the boom but its overriding advantage is met in manoeuvring in very confined waters such as a crowded dock or canal. From the deck, the sail can very readily be set or reduced by very small increments so as to control the power obtained from it. Meanwhile the boom does not project outboard so that the vessel can reach through a narrow gap between moored vessels. Also, the head of the sail or a similarly controlled topsail can readily be set so as to make use of the air above the wind-shadow of moored ships, warehouses and so on.

This fine control of the sail without need for the crew to leave the deck, is achieved by brailing up. Rather than lowering the mainsail
Mainsail
A mainsail is a sail located behind the main mast of a sailing vessel.On a square rigged vessel, it is the lowest and largest sail on the main mast....

, it is gathered up against its own luff and head by means of lines called brails. This technique is an effective way of stowing the mainsail but more importantly, it gives very fine control over the power obtained from the sail.

However, it means that the sail is stowed aloft and unreachable from the deck. It means that the sail cannot easily be covered when it is stowed, and thus protected from the elements. But in any case, the crews of working vessels did not trouble with such dainty ways. In keeping with the general philosophy of working boats, all sails would therefore be traditionally treated with red oxide and other substances.

The problem of the inaccessibility of gear was met in the Thames barge by stepping the mast in a tabernacle and using a windlass on the foredeck to strike the whole lot, mast, sprit, sails and rigging. A good crew could sail under a low bridge without losing steerage way. In the photograph, the windlass can be seen below the tack of the foresail and the tackle at the foot of the forestay, which was worked by the windlass, can be seen attached to the stem head. In striking the gear, the foresail tack tackle had to be cast off. The rest more or less looked after itself.

Dinghies

Modern use of the spritsail has also become more common through its use in the Optimist (dinghy)
Optimist (dinghy)
The Optimist is a small, single-handed sailing dinghy intended for use by children up to the age of 15. Nowadays boats are usually made of fiber reinforced plastic, although wooden boats are still built....

 - in the case of which the sprit is tensioned by a snotter
Snotter
A snotter is a rope or tackle used in sailing to tension the sprit on a spritsail, or a sprit boom on a sprit-boomed sail. It is also used in a junk rig....

 arrangement. This much simpler implementation sees the sprit anchored higher on the mast than on barges.

Local boats

The spiritsail is also commonly used in a fore-and-aft rig
Fore-and-aft rig
A fore-and-aft rig is a sailing rig consisting mainly of sails that are set along the line of the keel rather than perpendicular to it. Such sails are described as fore-and-aft rigged....

 (along with a staysail
Staysail
A staysail is a fore-and-aft rigged sail whose luff can be affixed to a stay running forward from a mast to the deck, the bowsprit or to another mast....

) on local traditional wooden boats of the west coast of Norway, most notably the faering
Faering
A faering is an open boat with two pairs of oars, commonly found in most boat-building traditions in Western and Northern Scandinavia.-History:...

 variant of the Oselvar
Oselvar
The Oselvar or Oselver is a small wooden rowing boat traditionally built and used along the west coast of Norway. The Oselvar is a clinker built boat with thin, very wide planks. Almost all parts of a Oselvar are made of pine, with only the keel of oak. -History:This type of boat has been very...


. Traditionally, upp till the second half of the 1800's; therse boats used to be rigged with a square rig
Square rig
Square rig is a generic type of sail and rigging arrangement in which the primary driving sails are carried on horizontal spars which are perpendicular, or square, to the keel of the vessel and to the masts. These spars are called yards and their tips, beyond the last stay, are called the yardarms...

.

External links

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