Rowing
Rowing is the act of propelling a human-powered watercraft using the sweeping motions of oars to displace water and generate reactional propulsion. Rowing is functionally similar to paddling, but rowing requires oars to be mechanically attached to the boat, and the rower drives the oar like a lever, exerting force in the same direction as the boat's travel; while paddles are completely hand-held and have no attachment to the boat, and are driven like a cantilever, exerting force opposite to the intended direction of the boat.
In some strict terminologies, using oars for propulsion may be termed either "pulling" or "rowing", with different definitions for each. Where these strict terminologies are used, the definitions are reversed depending on the context. On saltwater a "pulling boat" has each person working one oar on one side, alternating port and starboard along the length of the boat; whilst "rowing" means each person operates two oars, one on each side of the boat. On inland waterways, the opposite applies, with "rowing" being where each person in a crew works one oar and "sculling" involves each participant using a pair of oars. In a maritime setting "sculling" means propelling a boat with a single oar operated over the stern.
This article focuses on the general types of rowing, such as recreation and transport rather than the sport of competitive rowing, which is a specialized case of boat racing using strictly regulated equipment and a highly refined technique.
History of rowing
Ancient Egypt
The beginning of rowing is clouded in history but the use of oars in the way they are used today can be traced back to ancient Egypt. Whether it was invented in Egypt or something learned from Mesopotamia via trade is not known. However, archaeologists have recovered a model of a rowing vessel in a tomb dating back to the 18-19th century BC. The model they found was of a wide boat with shallow bottom, rather like a barge, which was designed to float on the shallow rivers of Mesopotamia. Both the Euphrates and the Tigris rivers were part of this region and flowing from the north to the south they quickly became an integral part of the non-nomadic civilizations.Rowing vessels, especially galleys, were extensively used in naval warfare and trade in the Mediterranean from classical antiquity onward. Galleys had advantages over sailing ships in light seas with low winds: they were easier to maneuver, capable of short bursts of speed, and able to move independently of the wind.
Ancient Greece
During the classical age of oared galleys, the Greeks dominated the Mediterranean while the Athenians dominated the other Greeks. They used thousands of lower-class citizens to serve as rowers in the fleet. In Classical Athens, a leading naval power at the time, rowing was regarded as an honorable profession of which men should possess some practical knowledge.The Classical trireme used 170 rowers; later galleys included even larger crews. Trireme oarsmen used leather cushions to slide over their seats, which allowed them to use their leg strength as a modern oarsman does with a sliding seat. Galleys usually had masts and sails, but would lower them at the approach of combat. Greek fleets would even leave their sails and masts on shore if possible.
Northern Europe
The use of oars in rowing instead of paddling came rather late to northern Europe, sometime between 500 BC-1 AD. This change might have been hastened by the Roman conquest of Northern Gaul. However, between 500 and 1100 AD, combined sailing and rowing vessels dominated trade and warfare in northern Europe in the time that has come to be known as the Viking Age.Galleys continued to be used in the Mediterranean until the advent of steam propulsion.
Types of rowing systems
In some localities, rear-facing systems prevail. In other localities, forward-facing systems prevail, especially in crowded areas such as in Venice, Italy and in Asian and Indonesian rivers and harbors. This is not strictly an "either-or", because in different situations it's useful to be able to row a boat facing either way. The current emphasis on the health aspects of rowing has resulted in some new mechanical systems being developed, some very different from the traditional rowing systems of the past.Rearward-facing systems
A seated rower pulls on one or two oars, which lever the boat through the water. The pivot point of the oars is the fulcrum for this lever. The person operating the oar is kept in position by a stretcher, a footrest that may be as simple as a wooden bar that can be adjusted by positioning in different pairs of notches in the bottom of the boat.Different types of pivot points can be used as a fulcrum for the oar.
- Thole pins are wooden pegs that are inserted into holes in the top of the gunwale. They are often used in pairs, with the oar resting between them. If used singly, the oar bears against the thole pin on the power stroke and is held in place by a leather strop for the return stroke.
- Oar crutchescommonly called "rowlocks" are metal fittings, usually U-shaped, with a pin underneath that fits into a metal socket on the gunwale. The oar sits in the U-shaped portion and the oar crutch pivots in the socket whilst in use.
- A rowlock or oarlock is, in strict terminology, a U-shaped cut-out in the top-most strake of the boat's hullthis cut-out is usually in a wash-strake, a strake that sits above the gunwale. A rowlock may be closed when, for instance, a boat is being used under sail. Strictly speaking, this is done with a piece called a shutter, which is habitually mistermed a "poppett".
- An oarport is a hole cut through the side of the hull. The oar has to be passed through this hole when it is needed. A slot may be cut in one part of the hole to allow the blade of the oar to get through.
Traditional boats propelled by oar are fitted with thwarts - seats that go from one side of the hull to the other, as well as forming part of the hull structure. A boat that is "double banked" has two crew members sitting on each thwart, each pulling an oar on their side of the boat. In a "single banked" boat, there is one person on each thwart pulling one oar. Though there is usually an even number of oars used in single banked boats a common exception is the arrangement in many whaleboats, where five oars were often used, three on one side and two on the other.
Forward-facing systems
Push rowing, also called back-watering if used in a boat not designed for forward motion, uses regular oars with a pushing motion to achieve forward-facing travel, sometimes seated and sometimes standing. This is a convenient method of manoeuvring in a narrow waterway or through a busy harbour.The Venetian rowing is the traditional technique in Venice, Italy in which the rower stands up, facing forward and resting a single oar in a special oarlock called fórcola.
The pletna of Slovenia is rowed forward in the standing position with two oars.
Another system involves using a single oar extending from the stern of the boat which is moved side to side underwater somewhat like a fish tail, such as the Chinese yuloh, by which quite large boats can be moved.
Sampans are rowed by foot in Ninh Bình Province of northern Vietnam.
The Intha people of Burma row forwards using their legs.
The "Rantilla" system of frontrowing oars uses inboard mounted oarlocks and a reversing transmission to achieve forward motion of the boat with a pulling motion on the oars.
Rowing propulsion
Rowing is a cyclic form of propulsion such that in the quasi-steady state the motion of the system, is repeated regularly. In order to maintain the steady-state propulsion of the system without either accelerating or decelerating the system, the sum of all the external forces on the system, averaged over the cycle, must be zero. Thus, the average drag force on the system must equal the average propulsion force on the system. The drag forces consist of aerodynamic drag on the superstructure of the system, as well as the hydrodynamic drag on the submerged portion of the system. The propulsion forces are the forward reaction of the water on the oars while in the water. The oar can be used to provide a drag force when the system is brought to rest.Although the oar can be conveniently thought of as a lever with a "fixed" pivot point in the water, the blade moves sideways and sternwards through the water, so that the magnitude of the propulsion force developed is the result of a complex interaction between unsteady fluid mechanics and solid mechanics and dynamics.
Distinction from other watercraft
The distinction between rowing and other forms of water transport, such as canoeing or kayaking, is that in rowing the oars are held in place at a pivot point that is in a fixed position relative to the boat. This point is the load point for the oar to act as a second-class lever. In flatwater rowing, the boat is narrow to avoid drag, and the oars are attached to oarlocks at the end of outriggers extending from the sides of the boat. Racing boats also have sliding seats to allow the use of the legs in addition to the body to apply power to the oar.Venetian rowing
In Venice, gondolas and other similar flat-bottomed boats are popular forms of transport propelled by oars which are held in place by an open wooden fórcola. The Voga alla Veneta technique of rowing is considerably different from the style used in international sport rowing, due to the oarsman facing forward in a standing position. This allows the boat to maneuver very quickly and with agility - useful in the narrow and busy canals of Venice. Competitive regattas are also held using the Venetian rowing technique by using both gondolas and other types of vessels.There are three styles of Venetian rowing, each slightly different. The first consists of a single oarsman with one oar, standing near the stern of the boat where the oar also acts as a rudder. The second style consists of one or two oarsmen, each with two crossed oars. The third style has two or more oarsmen, rowing on alternate sides of the boat.