Rowlock

A rowlock[1] UK: /ˈrɒlək/, sometimes spur (due to the similarity in shape and size), oarlock (USA)[2] or gate (Australia) is a brace that attaches an oar to a boat. When a boat is rowed, the rowlock acts as a fulcrum, and, in doing so, the propulsive force that the rower exerts on the water with the oar is transferred to the boat by the thrust force exerted on the rowlock.

On ordinary rowing craft, the rowlocks are attached to the gunwales. In the sport of rowing, the rowlocks are attached to outriggers (often just called "riggers"), which project from the boat and provide greater leverage. In sport rowing, the rowlocks are normally U-shaped and attached to a vertical pin which allows the rowlock to pivot around the pin during the rowing stroke. They additionally have a locking mechanism (properly known as "the gate") across the top of the "U" to prevent the oar from unintentionally popping out of the rowlock.

Originally, rowlocks were two wooden posts or thole pins that the shaft of the oar nestled between. Single THOLE PINS may be used when the oars have holes cut into the loom which then sits over/around the THOLE PIN. (Captain Dennis Robinson FNI, Master Mariner)

Oarlock (PSF)
A rowlock on a rowing boat
Rowing Sport Oarlock
A rowlock used for the sport of rowing

Sport rowing

In sport rowing oarlocks were originally brass or bronze and open (no gate). With the advent of modern materials oarlocks are now injection moulded plastic and precision made to minimize play (slop) between the oar collar and the oarlock. The most recent sport racing oarlocks have a spring loaded feature to keeps the oar collar firmly against the pin at all times.

Oarlocks are technical pieces of equipment in sport rowing, holding the oar shaft and therefore the oar blade at the correct angle in the water to ensure optimum performance.

Heraldry

The Norwegian municipalities of Fosnes, Radøy and Tjøme have rowlocks in their coats-of-arms.

References

  1. ^ "rowlock Meaning in the Cambridge English Dictionary". Retrieved 14 January 2017.
  2. ^ "Oarlock - definition and common misspellings". Retrieved 14 January 2017.
1937 European Rowing Championships

The 1937 European Rowing Championships were rowing championships for men held on the Bosbaan in the Dutch city of Amsterdam. The construction of the Bosbaan was an unemployment project, with the forest planted from 1934 onwards and the rowing lake finished in 1936. The rowers competed in all seven Olympic boat classes (M1x, M2x, M2-, M2+, M4-, M4+, M8+).

Anatomy of a rowing stroke

The two fundamental reference points in the anatomy of a rowing stroke are the catch where the oar blade is placed in the water, and the extraction (also known as the 'finish', 'release' or 'tapping down') where the oar blade is removed from the water. After the blade is placed in the water at the catch, the rower applies pressure to the oar levering the boat forward which is called the drive phase of the stroke. Once the rower extracts the oar from the water, the recovery phase begins, setting up the rower's body for the next stroke.

Bettendorf–Washington School

Bettendorf–Washington School was a historic building located in Bettendorf, Iowa, United States. It was listed on the National Register of Historic Places in 1984.

Brickwork

Brickwork is masonry produced by a bricklayer, using bricks and mortar. Typically, rows of bricks—called courses— are laid on top of one another to build up a structure such as a brick wall.

Bricks may be differentiated from blocks by size. For example, in the UK a brick is defined as a unit having dimensions less than 337.5x225x112.5mm and a block is defined as a unit having one or more dimensions greater than the largest possible brick.Brick is a popular medium for constructing buildings, and examples of brickwork are found through history as far back as the Bronze Age. The fired-brick faces of the ziggurat of ancient Dur-Kurigalzu in Iraq date from around 1400 BC, and the brick buildings of ancient Mohenjo-daro in Pakistan were built around 2600 BC. Much older examples of brickwork made with dried (but not fired) bricks may be found in such ancient locations as Jericho in Judea, Çatal Hüyük in Anatolia, and Mehrgarh in Pakistan. These structures have survived from the Stone Age to the present day.

Brick dimensions are expressed in construction or technical documents in two ways as co-ordinating dimensions and working dimensions.

Coordination dimensions are the actual physical dimensions of the brick with the mortar required on one header face, one stretcher face and one bed.

Working dimensions is the size of a manufactured brick. It is also called the nominal size of a brick.Brick size may be slightly different due to shrinkage or distortion due to firing etc.

An example of a co-ordinating metric commonly used for bricks in the UK is as follows:

Bricks of dimensions 215 mm × 102.5 mm × 65 mm;

Mortar beds and perpends of a uniform 10 mm.In this case the co-ordinating metric works because the length of a single brick (215 mm) is equal to the total of the width of a brick (102.5 mm) plus a perpend (10 mm) plus the width of a second brick (102.5 mm).

There are many other brick sizes worldwide, and many of them use this same co-ordinating principle.

Bushwick Democratic Club House

The Bushwick Democratic Club House was a notable building located in Brooklyn, New York. The building, designed by Brooklyn-based architect Frank Freeman in his signature Richardsonian Romanesque style, was completed in 1892, and designated a New York City landmark in the 1970s. It was later destroyed by fire.

Course (architecture)

A course is a layer of the same unit running horizontally in a wall. It can also be defined as a continuous row of any masonry unit such as bricks, concrete masonry units (CMU), stone, shingles, tiles, etc.Coursed masonry construction is that in which units are arranged in regular courses, and not irregularly. On the other hand, coursed rubble masonry construction is that in which units of random size, that are not cut down, are used to build courses and the in-between spaces are filled with mortar or smaller stones.If a course is the horizontal arrangement, then a wythe is the vertical section of a wall.A standard 8-inch CMU block is exactly equal to three courses of brick, so that is it easy to build a brick-on-CMU wall. A bond pattern (or bonding pattern) is the arrangement of several courses. The types of bond patterns can be found under Brickwork. When building a masonry wall the corners are first built and then the spaces between them are filled by the remaining courses.

Fórcola

Fórcola (Venetian dialect, plural Fórcole) is the typical Venetian rowlock providing a variety of fulcrum positions, each having its own effect on the rower's oar.

Glossary of British bricklaying

Air brick: A brick with perforations to allow the passage of air through a wall. Usually used to permit the ventilation of underfloor areas.

Bat: A cut brick. A quarter bat is one-quarter the length of a stretcher. A half-bat is one-half.

Bullnose: Rounded edges are useful for window sills, and capping on low and freestanding walls.

Cant: A header that is angled at less than 90 degrees.

Closer: A cut brick used to change the bond at quoins. Commonly a quarter bat.

Queens closer: A brick that has been cut over its length and is a stretcher long and a quarter-bat deep. Commonly used to bond one brick walls at right-angled quoins.

Kings closer: A brick that has been cut diagonally over its length to show a half-bat at one end and nothing at the other.

Coralent: A brick or block pattern that exhibits a unique interlocking pattern.

Corbel: A brick, block, or stone that oversails the main wall.

Cramp: Or frame cramp is a tie used to secure a window or door frame.

Creasing tile: A flat clay tile laid as a brick to form decorative features or waterproofing to the top of a garden wall.

Dog leg: A brick that is specially made to bond around internal acute angles. Typically 60 or 45 degrees.

Dog tooth: A course of headers where alternate bricks project from the face.

Fire wall: A wall specifically constructed to compartmentalise a building in order to prevent fire spread.

Header: A brick laid flat with its width exposed

Honeycomb wall: A wall, usually stretcher bond, in which the vertical joints are opened up to the size of a quarter bat to allow air to circulate. Commonly used in sleeper walls.

Indent: A hole left in a wall in order to accommodate an adjoining wall at a future date. These are often left to permit temporary access to the work area.

Movement joint: A straight joint formed in a wall to contain compressible material, in order to prevent cracking as the wall contracts or expands.

Noggin: Infill brick panels in timber framework buildings

Party wall: A wall shared by two properties or parties.

Pier: A free-standing section of masonry such as pillar or panel.

Plinth: A stretcher that is angled at less than 90 degrees.

Quoin: A corner in masonry.

Racking back: Stepping back the bond as the wall increases in height in order to allow the work to proceed at a future date.

Rowlock: A brick laid on the long narrow side with the short end of the brick exposed

Sailor: A brick laid vertically with the broad face of the brick exposed

Saw tooth: A course of headers laid at a 45-degree angle to the main face.

Shear wall: A wall designed to give way in the event of structural failure in order to preserve the integrity of the remaining building.

Shiner: A brick laid on the long narrow side with the broad face of the brick exposed

Sleeper wall: A low wall whose function is to provide support, typically to floor joists.

Snapped header: A half-bat laid to appear as a header. Commonly used to build short-radii half-brick walls or decorative features.

Soldier: A brick laid vertically with its long narrow side exposed

Squint: A brick that is specially made to bond around external quoins of obtuse angles. Typically 60 or 45 degrees.

Stopped end: The end of a wall that does not abut any other component.

Stretcher: A brick laid flat with its long narrow side exposed

Toothing: The forming of a temporary stopped end in such a way as to allow the bond to continue at a later date as the work proceeds.

Tumbling in: Bonding a battered buttress or breast into a horizontal wall.

Voussoir: A supporting brick in an arch, usually shaped to ensure that the joints appear even.

Withe: The central wall dividing two shafts. Most commonly to divide flues within a chimney.

Halsey Grocery Warehouse

The Halsey Grocery Warehouse is a historic warehouse in Huntsville, Alabama. It was built in 1923 as a second grocery warehouse for the W. L. Halsey company. The one-story building is simple in design, especially when compared with the company's earlier building across the street. The façade is of grey painted brick with a stepped parapet. The central double entrance door is flanked by single windows, each of which is topped with a brick arch. The pilasters and entablature surrounding the door are a later addition; originally, the door was topped only with a rowlock course of brick. The south side has a shed roof covering what was the loading area.The area of Jefferson Street was known as "Grocery Row", due to the number of grocery, vegetable, and fruit warehouses on the block. The Halsey Grocery Warehouse is adjacent to 305 Jefferson Street, the Kelly Brothers and Rowe Building, and the Lombardo Building, and is across the street from the W. L. Halsey Warehouse. The buildings lie one block south of the Huntsville Depot.The building was listed on the National Register of Historic Places in 1980.

Oar

An oar is an implement used for water-borne propulsion. Oars have a flat blade at one end. Rowers grasp the oar at the other end.

The difference between oars and paddles is that oars are used exclusively for rowing. In rowing the oar is connected to the vessel by means of a pivot point for the oar, either an oarlock, or a thole. The oar is placed in the pivot point with a short portion inside the vessel, and a much larger portion outside. The rower pulls on the short end of oar, while the long end is in the water. The oar is a second class lever with the water as the fulcrum, the oarlock as the load, and the rower as the force. An oar is an unusual lever since the mechanical advantage is less than one. The oar increases the small displacement of the end held by the rower, into a large displacement of the vessel through the water. The rower applies a large force through a small distance, which must be equaled by the small force the water applies opperating over a longer distance, i.e. the work done by the rower must be balanced by the work done by the water.By contrast, paddles, are held in both hands by the paddler, and are not attached to the vessel.

Rowers generally face the stern of the vessel, reach towards the stern, and insert the blade of their oar in the water. As they lean back, towards the vessel's bow, the blade of their oars pivots in the oarlock, and the end in the water moves towards the stern, providing forward thrust.

For thousands of years vessels were powered either by sails, or by the mechanical work of rowers, or by paddlers. Some ancient vessels were propelled by both oars and sail, depending on the speed and direction of the wind.

Oar (sport rowing)

In rowing, oars are used to propel the boat. Oars differ from paddles in that they use a fixed fulcrum, an oarlock or rowlock attached to the side of the boat, to transfer power from the handle to the blade, rather than using the athlete's shoulders or hands as the pivot-point as in canoeing and kayaking.

When the rower uses one oar on one side, it is called sweep rowing that the single oar is called a "sweep" oar. When the rower uses two oars at the same time, one on each side, it is called sculling, and the two oars are called a pair of "sculls". Typical sculls are around 284 cm - 290 cm in length — sweep oars are 370 cm - 376 cm. A scull has a smaller blade area, as each rower wields a pair of them at any one time, operating each with one hand. Since the 1980s many oars have been adjustable in length.

The shaft of the oar ends with a thin flat surface 40 to 50 cm long and 25 cm wide, variously called the blade or spoon. Further along are the loom (or shaft), 2/3 of the way up which is the sleeve (including a wearplate) and button (or collar), and at the very end the handle. The handle may revert to wooden or, particularly in the case of sculls and some 21st century models of sweep-oar blades have rubber, cellular foam, suede or for example wood veneer grips over glass fiber.

The part of the oar the rower holds while rowing is the handle which is longer for sweep blades as each is held using both hands, than for sculls which are held with one hand.

There are hundreds of different variations of oars in terms of size and manufacturer specifications. "Macon" or "Cleaver" blade shapes of carbon-fibre are the most common in modern-day rowing. Classic oars were made out of wood. Since the use of such synthetic materials, first mass-produced by Dreissigacker in 1975, the weight of an oar has come down from over 7 kg to less than 2.5 kg and 1.275-1.8 kg in the case of sculls. While rowing in the most common competitive boats, fine boats (racing shells), oars are since the early part of the 20th century supported by metal, fibreglass or carbon fibre frames attached to the side of the boat called riggers for extra leverage.

Outrigger

An outrigger is a projecting structure on a boat, with specific meaning depending on types of vessel. Outriggers may also refer to legs on a wheeled vehicle which are folded out when it needs stabilization, for example on a crane that lifts heavy loads.

Rowing

Rowing is the act of propelling a boat using the motion of oars in the water by displacing water to propel the boat forward. Rowing and paddling are similar but the difference is that rowing requires oars to have a mechanical connection with the boat, while paddles (used for paddling) are hand-held and have no mechanical connection.

This article focuses on the general types of rowing, such as the recreation and the transport rather than the sport of competitive rowing which is a specialized case of racing using strictly regulated equipment and a highly refined technique.

Saint Leonard Catholic Church (Madison, Nebraska)

Saint Leonard Catholic Church is a Roman Catholic church in the city of Madison, in the state of Nebraska in the Midwestern United States. Built in 1913, it has been described as "an outstanding example of the Romanesque Revival style of architecture."St. Leonard's parish, named after Saint Leonard of Port Maurice, was organized in 1879. A wood frame church was built in 1881 on the outskirts of Madison, and moved into the city in 1898. In 1902, the basement of the current church was built, and the congregation moved into it, converting the old church to a school. When funds allowed, the basement was extended, and the current brick church completed in 1913.

In 1989, the church, its 1912 rectory, and the rectory's garage were listed in the National Register of Historic Places, as the work of noted Nebraska architect Jacob M. Nachtigall. A pupil of Thomas Rogers Kimball, Nachtigall designed a number of Catholic churches and other buildings in the state, several of which are also listed in the National Register.

Sam Henry (musicologist)

Samuel Henry (9 May 1878 – 23 May 1952), known as Sam Henry, was an Irish customs officer, pension officer, antiquarian, lecturer, writer, photographer, folklorist, and folk-song collector. He also played the fiddle and the tin whistle.

He is best known for his collection of ballads and songs in Songs of the People, the largest and most comprehensive collection of folk-songs from Northern Ireland assembled between the wars (1923 – 1939), when he was Song Editor for the Northern Constitution, a weekly newspaper in Coleraine.

Sculling

Sculling is the use of oars to propel a boat by moving the oars through the water on both sides of the craft, or moving a single oar over the stern. By extension, the oars themselves are often referred to as sculls when used in this manner, and the boat itself may be referred to as a scull.

Terry Hutchens Building

The Terry Hutchens Building is a historic office and apartment building in Huntsville, Alabama. The seven story structure was originally constructed in 1925 for the Tennessee Valley Bank, with office space rented to other tenants. In 2002, the upper floors were renovated into condominiums. The structure is of steel reinforced concrete faced with brick, giving a Gothic Revival appearance. The ground floor façade has large display windows separated by brick piers, and has a central, arched entry covered in masonry. The Jefferson Street façade was originally treated the same way, but was modified with a flat wall of thin brick above two storefront entrances. A decorative band with rowlock course brick and terra cotta panels separate the ground floor from the rest of the building. Above, the piers divide each bay containing a pair of one-over-one sash windows; on the seventh floor, a green terra cotta frog sits on the sill, between the windows. Each bay of the cornice is divided by terra cotta decorated with Gothic shapes and medallions on panels of brick. The building was listed on the National Register of Historic Places in 1980.

The Boat Race 1902

The 59th Boat Race took place on 22 March 1902. Held annually, the Boat Race is a side-by-side rowing race between crews from the Universities of Oxford and Cambridge along the River Thames. Although Oxford used swivel rowlocks for the first time in the history of the race, Cambridge won by five lengths in a time of 19 minutes 9 seconds. The victory took the overall record to 33–25 in Oxford's favour.

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