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Definição e significado de Rowboat

Definição

rowboat (n.)

1.(American)a small boat of shallow draft with cross thwarts for seats and rowlocks for oars with which it is propelled

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Merriam Webster

RowboatRow"boat` (?), n. A boat designed to be propelled by oars instead of sails.

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Definiciones (más)

definição - Wikipedia

Sinónimos

rowboat (n.) (American)

dinghy, dory, rowing boat  (British)

Ver também

rowboat (n.)

row

Locuções

Dicionario analógico

Wikipedia

Watercraft rowing

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Rowing in the Amstel River by a student rowing club.

Watercraft rowing is the act of propelling a boat using the motion of oars in the water. The difference between paddling and rowing is that with rowing the oars have a mechanical connection with the boat whereas with paddling the paddles are hand-held with no mechanical connection.

This article deals with general rowing including the recreational, transportation and utility aspects of rowing, rather than the sport of competitive rowing which is a specialized case of racing using strictly regulated equipment and a highly refined technique[1].

Contents

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:This is probably the oldest system used in Europe and North America. A seated rower pulls on one or two oars, which lever the boat through the water. The pivot point of the oars (attached solidly to the boat) is the fulcrum. The motive force is applied through the rower's feet.In traditional rowing craft, the pivot point of the oars is generally located on the boat's gunwale. The actual fitting that holds the oar may be as simple as one or two pegs (or thole pins) or a metal oarlock (also called rowlock - "rollock"). In performance rowing craft, the rowlock is usually extended outboard on a "rigger" to allow using a longer oar for increased power.

Sculling involves a seated rower who pulls on two oars or sculls, attached to the boat, thereby moving the boat in the direction opposite that which the rower faces. In some multiple-seat boats seated rowers each pull on a single "sweep" oar. Boats in which the rowers are coordinated by a coxswain are referred to as a "coxed" pair/four/eight. Sometimes sliding seats are used to enable the rower to use the leg muscles, substantially increasing the power available. An alternative to the sliding seat, called a sliding rigger, uses a stationary seat and the rower moves the oarlocks with his feet. On a craft used in Italy, the catamaran moscone, the rower stands and takes advantage of his body weight to increase leverage while sculling.[2]

Forward facing systems:Articulated or bow facing oars have two-piece oars and use a mechanical transmission to reverse the direction of the oar blade, enabling a seated rower to row facing forward with a pulling motion. 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. Another system uses inboard mounted oarlocks to achieve forward motion of the boat with a pulling motion on the oars.

Another system (also called sculling) involves using a single oar extending from the stern of the boat which is moved back and forth under water somewhat like a fish tail, such as the Chinese yuloh, by which quite large boats can be moved.[citation needed]

Ancient rowing

File:Abraham Willaerts, Galley and men of war.jpeg
A French galley and Dutch men-of-war off a port

In ancient times, rowing boats (known as galleys) were extensively used during war, in particular in the Mediterranean in classical antiquity. Galleys had advantages over sailing ships; they may be easier to manoeuvre, quicker in sprints, and able to move independent of the wind. Galleys continued in use in the Mediterranean until the advent of steam propulsion. Their use in northern Atlantic waters was less successful, finishing with their disappointing performance with the Spanish Armada.

The classic trireme used 170 rowers; later galleys included even larger crews. Trireme oarsmen used leather cushions to slide over the 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 when about to enter combat would lower them. Greek fleets would also leave their sails and masts on shore (as being unnecessary weight) if possible.[3]

Venetian rowing

A Gondola in Venice

In Venice, gondolas and other similar flat bottomed boats[4] are popular forms of transport propelled by oars which are held in place by an open wooden fòrcola[5]. The Voga alla Veneta[6] 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 manoeuover very quickly and with agility - useful in the narrow and busy canals of Venice. Competitive regattas are also held using the Venetian rowing technique, using both gondolas and other types of vessels.

There are three different styles of Venetian rowing:

  1. Single oarsman with one oar, standing near the stern of the boat (the oar also acts as a rudder)
  2. One or two oarsman each with two crossed oars (known as a la valesàna)
  3. Two or more oarsmen, rowing on alternate sides of the boat

Whitehall Rowboats

The origins of this distinctively elegant and extremely practical craft are unclear. In earlier times, however, builders were often sailors or seafaring men. Taught by the sea to be conservative, they stuck with the tried and true. Successful designs for large and small craft alike evolved slowly and as certain desirable qualities were attained and perfected they rarely changed.

Some hold that the Whitehall rowing boat design was introduced from England. However the famed nautical historian Howard I. Chapelle, cites the opinion of the late W. P. Stephens that in New York City there is a Whitehall Street and this was where the Whitehall was first built. Chapelle, Stephens and others agree that the design came into existence some time in the 1820s in New York City, having first been built by navy yard apprentices who had derived their model to some extent from the old naval gig.

In Wooden Boats to Build and Use (1996), John Gardner of Mystic Seaport describes a 25-foot racing Whitehall, named American Star, which triumphed in an 1824 race in New York Harbor that according to newspapers of the time drew 50,000 spectators, more than any American sporting event ever until then. The following year the boat was gifted to an ageing General Lafayette, hero of the American Revolution, during his tour of the U.S. The American Star returned to Lafayette's estate in France where it was displayed in a specially constructed gazebo. During the mid 20th century the boat was rediscovered in storage there, and its lines have be preserved at Mystic Seaport where an exact replica was built in 1974-75, and still rows at Seaport events.


What makes a good rowboat

There are many considerations that go into selecting a good rowboat. A well designed rowboat will perform well in trying conditions. The classic shapes of rowboats reflect an evolution of hundreds of years old trial and error to get a good shape. Some factors that have to be considered are waterline length, speed, carrying capacity, stability, windage, weight, seaworthiness, cost, waterline beam, the fullness or fineness of the ends, trim and more.

Dealing with these issues in more detail it can be seen that these details are a compromise between competing factors. Example if the waterline beam (width) is too narrow the boat will be tender and the occupant at risk of falling out, if the beam is too high the boat will be slow and be caught up with the waves. Another issue is windage and freeboard, if the freeboard (height of the gunnel above the waterline) is too high then windage will be high and as a result the boat will be caught by the wind and the rower will not be able to control the boat in high winds, if the freeboard is too low, water will enter the boat through waves.

Another issue is trim, if the boat is designed for one person then only a single rowing position is required. If the rower is to carry a passenger at the stern then the boat will be stern heavy and trim will be out. To correct this a weight can be added to the bow, alternatively the boat can supply a second rowing position further forward for this purpose. For a boat to carry three separate thwarts as described and with adequate space for each occupant then the boat has to be of a certain minimum size. It is oft quoted that the ideal size of a good rowboat is 15ft.

Overall beam (width) is important too. If the rowlocks are too close together the oars will be difficult to use. If the rowlocks are too far apart then the boat will be overly large. Sometimes on faster rowboats for protected waters outriggers are added to increase rowlock separation. Many traditional rowboats have a beam of about 4.5ft.

Many old rowboats have very full ends (blunt ends), these may appear at first glance to be bad design as it looks slow, not fast. However a full ended rowboat will rise to a sea and not dig in as a finer hulled boat might do, thus a compromise needs to be made between the factors of speed and of seaworthiness.

Speed, a rowboat designed for carrying occupants to a boat berthed at a mooring might tend to be short and beamy, whilst a rowboat for use on rivers and to travel long distances might be long and narrow.

It can be seen that just by discussing a few issues that the design of a good classic rowboat is a very ingenious and sophisticated solution to the task of keeping people alive on the sea. Men who spent all their working lives at sea needed boats that would bring them safely home, the classic boats that were derived from this task, be they rowboats or otherwise are the end result of hundreds of years of evolution to the optimum solution

A Sunnmørsfæring; a Norwegian 4-oared rowing boat, from the region Sunnmøre (Herøy kystmuseum, Herøy, Møre og Romsdal, Norway)

See also

References

  1. ^ "Speed Rower, Competitive Rowing". http://www.speedrower.com/index.htm. Retrieved 2009-02-05. 
  2. ^ http://www.settesere.it/public/parser_download/save/allegati.2007.32.pag04.e05due.pdf Remando in piedi sul moscone. (Rowing standing up on the moscone).
  3. ^ The Athenian Trireme: The History and Reconstruction of an Ancient Greek Warship. J. S. Morrison, J. F. Coates, N. B. Rankov. Publisher: Cambridge University Press; 2 edition (20 Jul 2000), ISBN 0521564565, ISBN 978-0521564564
  4. ^ Le barche at www.vogaveneta.it (Italian)
  5. ^ La forcola - le barche per la Voga alla Veneta at www.vogaveneta.it (Italian)
  6. ^ Venetian rowing technique at www.venetia.it

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