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68-498: There are two yards (6 feet ) in an imperial fathom. Originally the span of a man's outstretched arms , the size of a fathom has varied slightly depending on whether it was defined as a thousandth of an (Admiralty) nautical mile or as a multiple of the imperial yard . Formerly, the term was used for any of several units of length varying around 5– 5 + 1 ⁄ 2 feet (1.5–1.7 m). The term (pronounced / ˈ f æ ð ə m / ) derives (via Middle English fathme ) from

136-645: A piezoelectric transmitter ). His work was developed and implemented by other scientists and technnicians such as Chilowski, Florisson and Pierre Marti. Though a fully operational échosondeur (sonar) was not ready for use in wartime, there were successful trials both off Toulon and in the English Channel as early as 1920, and French patents taken for civilian uses. Oceanographic ships and French high-sea fishing assistance vessels were equipped with Langevin-Florisson and Langevin Marti recording sonars as early as

204-413: A quarter meant one-quarter of a fathom. A cable length , based on the length of a ship's cable, has been variously reckoned as equal to 100 or 120 fathoms. Most modern nautical charts indicate depth in metres. However, the U.S. Hydrographic Office uses feet and fathoms. A nautical chart will always explicitly indicate the units of depth used. To measure the depth of shallow waters, boatmen used

272-432: A sounding line containing fathom points, some marked and others in between, called deeps , unmarked but estimated by the user. Water near the coast and not too deep to be fathomed by a hand sounding line was referred to as in soundings or on soundings . The area offshore beyond the 100 fathom line, too deep to be fathomed by a hand sounding line, was referred to as out of soundings or off soundings . A deep-sea lead ,

340-646: A brass ell at the Guildhall ; and a brass yard presented to the Clock-Makers' Company by the Exchequer in 1671. The Exchequer yard was taken as "true"; the variation was found to be + 1 ⁄ 20 to − 1 ⁄ 15 of an inch, and an additional graduation for the Exchequer yard was made on the Royal Society's standard. In 1758 the legislature required the construction of a standard yard, which

408-626: A commission was formed to reconstruct the lost standards, including the troy pound, which had also been destroyed. In 1845, a new yard standard was constructed based on two previously existing standards known as A1 and A2, both of which had been made for the Ordnance Survey, and R.S. 46, the yard of the Royal Astronomical Society . All three had been compared to the Imperial standard before the fire. The new standard

476-486: A committee of parliament proposed defining the standard yard based upon the length of a seconds pendulum . This idea was examined but not approved. The Weights and Measures Act 1824 ( 5 Geo. 4 . c. 74) An Act for ascertaining and establishing Uniformity of Weights and Measures stipulates that: In 1834, the primary Imperial yard standard was partially destroyed in a fire known as the Burning of Parliament . . In 1838,

544-466: A number of different marine robotic vehicles. It operates by using a transducer to emit a pulse through the water and listen for echos to return. Using that data, it's able to determine the distance from the strongest echo, which can be the seafloor, a concrete structure, or other larger obstacle. A fishfinder is an echo sounding device used by both recreational and commercial fishers. As well as an aid to navigation (most larger vessels will have at least

612-422: A piece of one quarter yard cut from the full width of the roll; these pieces are popular for patchwork and quilting . The term "fat eighth" is also used, for a piece of one quarter yard from half the roll width, the same area as one eighth cut from the roll. For purposes of measuring cloth, the early yard was divided by the binary method into two, four, eight and sixteen parts. The two most common divisions were

680-602: A pulse; the resulting time of flight , along with knowledge of the speed of sound in water, allows determining the distance between sonar and target. This information is then typically used for navigation purposes or in order to obtain depths for charting purposes. Echo sounding can also be used for ranging to other targets, such as fish schools . Hydroacoustic assessments have traditionally employed mobile surveys from boats to evaluate fish biomass and spatial distributions. Conversely, fixed-location techniques use stationary transducers to monitor passing fish. The word sounding

748-429: A simple depth sounder), echo sounding is commonly used for fishing . Variations in elevation often represent places where fish congregate. Schools of fish will also register. In areas where detailed bathymetry is required, a precise echo sounder may be used for the work of hydrography. There are many considerations when evaluating such a system, not limited to the vertical accuracy, resolution, acoustic beamwidth of

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816-837: A yard and a quarter, or 45 inches. The ell was borrowed from the Paris drapers. Subsequently, however, Queen Elizabeth re-introduced the yard as the English standard of measure. The earliest record of a prototype measure is the statute II Edgar Cap. 8 (AD 959  x 963), which survives in several variant manuscripts. In it, Edgar the Peaceful directed the Witenagemot at Andover that "the measure held at Winchester " should be observed throughout his realm. (Some manuscripts read "at London and at Winchester".) The statutes of William I similarly refer to and uphold

884-593: Is aforesaid, and in Breadth one Yard of like Measure; (3) and every such Cloth, both Broad and Narrow being well scowred , thicked, milled and fully dried, shall weigh xxxiv. li. the Piece at the least. XV. And that all Clothes named Check- Kersie and Straits , which shall be made after the said Feast shall contain being wet between seventeen and eighteen Yards, with the Inches as is aforesaid, and in Breadth one Yard at

952-640: Is an extension of a dual frequency vertical beam echosounder in that, as well as measuring two soundings directly below the sonar at two different frequencies; it measures multiple soundings at multiple frequencies, at multiple different grazing angles, and multiple different locations on the seabed. These systems are detailed further in the section called multibeam echosounder . Echo sounders are used in laboratory applications to monitor sediment transport, scour and erosion processes in scale models (hydraulic models, flumes etc.). These can also be used to create plots of 3D contours. The required precision and accuracy of

1020-436: Is approximately 1.5 kilometres per second. The speed of sound will vary slightly depending on temperature, pressure and salinity; and for precise applications of echosounding, such as hydrography , the speed of sound must also be measured, typically by deploying a sound velocity probe in the water. Echo sounding is a special purpose application of sonar used to locate the bottom. Since a historical pre- SI unit of water depth

1088-502: Is attested in a statute of c.  1300 ( see below ), but there it is called an ell ( ulna , lit.  " arm "), a separate and usually longer unit of around 45 inches (1,100 mm). The use of the word ‘yard’ ( Middle English : ȝerd or ȝerde ) to describe this length is first attested in William Langland 's poem on Piers Plowman . The usage seems to derive from the prototype standard rods held by

1156-483: Is equal to 1 mile . The US survey yard is very slightly longer. The term, yard derives from the Old English gerd , gyrd etc., which was used for branches , staves and measuring rods . It is first attested in the late 7th century laws of Ine of Wessex , where the "yard of land" mentioned is the yardland , an old English unit of tax assessment equal to 1 ⁄ 4   hide . Around

1224-713: Is equal to: In the international yard and pound agreement of 1959 the United States , Australia , Canada , New Zealand , South Africa , and the United Kingdom defined the length of the international yard to be exactly 0.9144 metre . In 1959 United States kept the US survey foot as definition for the fathom. In October 2019, the U.S. National Geodetic Survey and the National Institute of Standards and Technology announced their joint intent to retire

1292-433: Is known as "Bronze Yard No. 11" The Weights and Measures Act 1878 ( 41 & 42 Vict. c. 49) confirmed the status of the existing yard standard, mandated regular intercomparisons between the several yard standards, and authorized the construction of one additional Parliamentary Copy (made in 1879 and known as Parliamentary Copy VI). Subsequent measurements revealed that the yard standard and its copies were shrinking at

1360-506: Is occasionally used: 1 ⁄ 1000 nautical mile or 1 ⁄ 100 cable length . A burial at sea (where the body is weighted to force it to the bottom) requires a minimum of six fathoms of water. This is the origin of the phrase " to deep six" as meaning to discard, or dispose of. The phrase is echoed in Shakespeare's The Tempest , where Ariel tells Ferdinand , " Full fathom five thy father lies". Until early in

1428-444: Is used for all types of depth measurements, including those that don't use sound , and is unrelated in origin to the word sound in the sense of noise or tones. Echo sounding is a more rapid method of measuring depth than the previous technique of lowering a sounding line until it touched bottom. German inventor Alexander Behm was granted German patent No. 282009 for the invention of echo sounding (device for measuring depths of

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1496-499: Is usually translated as "fathom". By the Byzantine period , this unit came in two forms: a "simple orguia" ( ἁπλὴ ὀργυιά , haplē orguiá ) roughly equivalent to the old Greek fathom (6 Byzantine feet , c.  1.87   m ) and an "imperial" ( βασιλικὴ , basilikē ) or "geometric orguia" ( γεωμετρικὴ ὀργυιά , geōmetrikē orguiá ) that was one-eighth longer (6 feet and a span , c.  2.10   m). One fathom

1564-632: The Old English fæðm , which is cognate with the Danish word favn (via the Vikings) and means "embracing arms" or "pair of outstretched arms". It is maybe also cognate with the Old High German word "fadum", which has the same meaning and also means "yarn (originally stretching between the outstretched fingertips)". The Ancient Greek measure known as the orguia ( ‹See Tfd› Greek : ὀργυιά , orgyiá , lit .   "outstretched")

1632-863: The Statute for the Measuring of Land . The act was not repealed until the Weights and Measures Act 1824 . In a law of 1439 ( 18 Hen. 6 . c. 16) the sale of cloth by the "yard and handful" was abolished, and the "yard and inch" instituted (see ell ). There shall be but one Measure of Cloth through the Realm by the Yard and the Inch , and not by the Yard and Handful , according to the London Measure. According to Connor, cloth merchants had previously sold cloth by

1700-601: The Weights and Measures Act 1963 . The Imperial Standard Yard of 1855 was renamed the United Kingdom Primary Standard Yard and retained its official status as the national prototype yard. The yard is used as the standard unit of field-length measurement in American , Canadian and association football , cricket pitch dimensions, and in some countries, golf fairway measurements. There are corresponding units of area and volume ,

1768-472: The Welsh used multiples of a shorter foot , but 2 + 1 ⁄ 2   Roman feet was a " step " (Latin: gradus ) and 3  Welsh feet was a " pace " ( Welsh : cam ). The Proto-Germanic cubit or arm's-length has been reconstructed as * alinô , which developed into the Old English eln , Middle English elne , and modern ell of 1.25 yd (1.14 m). This has led some to derive

1836-498: The iron yard of our Lord the King containeth 3 feet and no more, and a foot ought to contain 12 inches by the right measure of this yard measured, to wit, the 36th part of this yard rightly measured maketh 1 inch neither more nor less and 5 yards and a half make a perch that is 16 feet and a half measured by the aforesaid yard of our Lord the King. In some early books, this act was appended to another statute of uncertain date titled

1904-540: The square yard and cubic yard respectively. These are sometimes referred to simply as "yards" when no ambiguity is possible, for example an American or Canadian concrete mixer may be marked with a capacity of " 9 yards " or "1.5 yards", where cubic yards are obviously referred to. Yards are also used and are the legal requirement on road signs for shorter distances in the United Kingdom, and are also frequently found in conversation between Britons much like in

1972-420: The 20th century, it was the unit used to measure the depth of mines (mineral extraction) in the United Kingdom . Miners also use it as a unit of area equal to 6 feet square (3.34 m) in the plane of a vein. In Britain, it can mean the quantity of wood in a pile of any length measuring 6 feet (1.8 m) square in cross section. In Central Europe , the klafter was the corresponding unit of comparable length, as

2040-707: The Royal Mint, the Royal Society of London, the Royal Observatory at Greenwich, and the New Palace at Westminster, commonly called the Houses of Parliament. The other 35 yard standards were distributed to the cities of London, Edinburgh, and Dublin, as well as the United States and other countries (although only the first five had official status). The imperial standard received by the United States

2108-510: The U.S. survey foot, with effect from the end of 2022. The fathom in U.S. Customary units is thereafter defined based on the International 1959 foot, giving the length of the fathom as exactly 1.8288 metres in the United States as well. The British Admiralty defined a fathom to be a thousandth of an imperial nautical mile (which was 6080 ft) or 6.08 feet (1.85 m). In practice the "warship fathom" of exactly 6 feet (1.8 m)

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2176-407: The United States for distance. The yard, subdivided into eighths, is used for the purchase of fabrics in the United States and United Kingdom and was previously used elsewhere. In the United States the term "fat quarter" is used for a piece of fabric which is half a yard in length cut from a roll and then cut again along the width so that it is only half the width of the roll, thus the same area as

2244-471: The ability to identify a vegetation layer or a layer of soft mud on top of a layer of rock. Most hydrographic operations use a 200 kHz transducer, which is suitable for inshore work up to 100 metres in depth. Deeper water requires a lower frequency transducer as the acoustic signal of lower frequencies is less susceptible to attenuation in the water column. Commonly used frequencies for deep water sounding are 33 kHz and 24 kHz. The beamwidth of

2312-522: The de facto legal definition of the yard came to be accepted as 36 ⁄ 39.370 113 of a meter. The yard (known as the "international yard" in the United States) was legally defined to be exactly 0.9144 meter in 1959 under an agreement in 1959 between Australia, Canada, New Zealand, South Africa, the United Kingdom and the United States. In the UK, the provisions of the treaty were ratified by

2380-405: The fourth and sixteenth parts. The quarter of a yard (9 inches) was known as the "quarter" without further qualification, while the sixteenth of a yard (2.25 inches) was called a nail . The eighth of a yard (4.5 inches) was sometimes called a finger , but was more commonly referred to simply as an eighth of a yard, while the half-yard (18 inches) was called "half a yard". Other units related to

2448-458: The heave component (in single beam echosounding) to reduce soundings for the motion of the vessel experienced on the water's surface. Once all of the uncertainties of each sensor are established, the hydrographer will create an uncertainty budget to determine whether the survey system meets the requirements laid down by IHO. Different hydrographic organisations will have their own set of field procedures and manuals to guide their surveyors to meet

2516-471: The heaviest of sounding leads, was used in water exceeding 100 fathoms in depth. This technique has been superseded by sonic depth finders for measuring mechanically the depth of water beneath a ship, one version of which is the Fathometer (trademark). The record made by such a device is a fathogram . A fathom line or fathom curve , a usually sinuous line on a nautical chart, joins all points having

2584-459: The human body, such as a foot, the length of the arm, the span of the hand, or from other natural objects, such as a barleycorn, or other kind of grain. But the yard was the original standard adopted by the early English sovereigns, and has been supposed to be founded upon the breadth of the chest of the Saxon race. The yard continued till the reign of Henry VII., when the ell was introduced, that being

2652-595: The hydrographic echo sounder is defined by the requirements of the International Hydrographic Organization (IHO) for surveys that are to be undertaken to IHO standards. These values are contained within IHO publication S44. In order to meet these standards, the surveyor must consider not only the vertical and horizontal accuracy of the echo sounder and transducer, but the survey system as a whole. A motion sensor may be used, specifically

2720-456: The king and his magistrates ( see below ). The word ‘yard’ is a homonym of ‘yard’ in the sense of an enclosed area of land . This second meaning of ‘yard’ has an etymology related to the word ‘garden’ and is not related to the unit of measurement. In India Yard is colloquially known as Gauge or Guz . 1 Gauge is 3 feet. The origin of the yard measure is uncertain. Both the Romans and

2788-458: The least at the Water; and being well scowred, thicked, milled and fully dried, shall weigh xxiv. li. the Piece at the least. The yard and inch for cloth measurement was also sanctioned again in legislation of 1557–1558 ( 4 & 5 Ph. & M. c. 5. An act touching the making of woolen clothes. par. IX.) IX. Item, That every ordinary kersie mentioned in the said act shall contain in length in

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2856-661: The mid/late 1920s. One of the first commercial echo sounding units was the Fessenden Fathometer, which used the Fessenden oscillator to generate sound waves. This was first installed by the Submarine Signal Company in 1924 on the M&;M liner SS Berkshire. Distance is measured by multiplying half the time from the signal's outgoing pulse to its return by the speed of sound in water, which

2924-408: The middle, was used to take fish from a larger seine . A line attached to a whaling harpoon was about 150 fathoms (900 ft; 270 m). A forerunner — a piece of cloth tied on a ship's log line some fathoms from the outboard end — marked the limit of drift line. A kite was a drag, towed under water at any depth up to about 40 fathoms (240 ft; 73 m), which upon striking bottom,

2992-464: The opening of the annual St. Bartholomew's Day Cloth Fair . In the mid-18th century, Graham compared the standard yard of the Royal Society to other existing standards. These were a "long-disused" standard made in 1490 during the reign of Henry VII , and a brass yard and a brass ell from 1588 in the time of Queen Elizabeth and still in use at the time, held at the Exchequer ; a brass yard and

3060-568: The rate of one part per million every twenty years due to the gradual release of strain incurred during the fabrication process. The international prototype meter , on the other hand, was comparatively stable. A measurement made in 1895 determined the length of the meter at 39.370 113 inches relative to the imperial standard yard. The Weights and Measures (Metric System) Act 1897 ( 60 & 61 Vict. c. 46) in conjunction with Order in Council 411 (1898) made this relationship official. After 1898,

3128-453: The reign of Edward I or II c.  1300 . Its wording varies in surviving accounts. One reads: It is ordained that 3 grains of barley dry and round do make an inch , 12 inches make 1 foot , 3 feet make 1 yard, 5 yards and a half make a perch , and 40 perches in length and 4 in breadth make an acre . The Liber Horn compilation (1311) includes that statute with slightly different wording and adds: And be it remembered that

3196-562: The rule,... One of the oldest yard-rods in existence is the clothyard of the Worshipful Company of Merchant Taylors . It consists of a hexagonal iron rod 5 ⁄ 8  in (16 mm) in diameter and 1 ⁄ 100  in (0.25 mm) short of a yard, encased within a silver rod bearing the hallmark 1445. In the early 15th century, the Merchant Taylors Company was authorized to "make search" at

3264-580: The said Feast in Taunton, Bridgwater or in other Places of like Sort, shall contain at the Water in Length betwixt twelve and thirteen Yards, Yard and Inch of the Rule, and in Breadth seven Quarters of a Yard: (2) And every narrow Cloth made after the said Feast in the said Towns or elsewhere of like Sorts, shall contain in the Water in Length betwixt three and twenty and five and twenty Yards, Yard and Inch as

3332-586: The same depth of water, thereby indicating the contour of the ocean floor. Some extensive flat areas of the sea bottom with constant depth are known by their fathom number, like the Broad Fourteens or the Long Forties , both in the North Sea . The components of a commercial fisherman's setline were measured in fathoms. The rope called a groundline , used to form the main line of a setline,

3400-611: The same time the Lindisfarne Gospels account of the messengers from John the Baptist in the Gospel of Matthew used it for a branch swayed by the wind. In addition to the yardland, Old and Middle English both used their forms of "yard" to denote the surveying lengths of 15 feet (4.6 m) or 16.5 feet (5.0 m), used in computing acres , a distance now usually known as the " rod ". A unit of three English feet

3468-468: The sea and distances and headings of ships or obstacles by means of reflected sound waves) on 22 July 1913. Meanwhile, in France, physicist Paul Langevin (connected with Marie Curie and better known for his research work in nuclear physics ) was recruited by French Navy laboratories at the beginning of World War 2 and conducted (then secret) research on active sonars for anti-submarine warfare (using

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3536-529: The standard measures of his predecessors without naming them. William of Malmesbury 's Deeds of the Kings of England records that during the reign of Henry I (1100 - 1135), "the measure of his arm was applied to correct the false ell of the traders and enjoined on all throughout England." The folktale that the length was bounded by the king's nose was added some centuries later. Charles Moore Watson dismisses William's account as "childish", but William

3604-460: The temperature, pressure and salinity. These factors are used to estimate more accurately the actual sound speed in the local water column. This technique is often used by the US Office of Coast Survey for navigational surveys of US coastal waters. A single-beam echo sounder is one of the simplest and most fundamental types of underwater sonar. They are ubiquitous in the boating world and used on

3672-454: The thirty-fourth year of the reign of our sovereign lady the Queen that now is. par. III.) (2) and each and every of the same Devonshire kersies or dozens, so being raw, and as it cometh forth off the weaver's loom (without racking, stretching, straining or other device to encrease the length thereof) shall contain in length between fifteen and sixteen yards by the measure of yard and inch by

3740-427: The transducer is also a consideration for the hydrographer, as to obtain the best resolution of the data gathered a narrow beamwidth is preferable. The higher the operating frequency, the narrower the beamwidth. Therefore, it is especially important when sounding in deep water, as the resulting footprint of the acoustic pulse can be very large once it reaches a distant sea floor. A multispectral multibeam echosounder

3808-465: The transmit/receive beam and the acoustic frequency of the transducer . The majority of hydrographic echosounders are dual frequency, meaning that a low frequency pulse (typically around 24 kHz) can be transmitted at the same time as a high frequency pulse (typically around 200 kHz). As the two frequencies are discrete, the two return signals do not typically interfere with each other. Dual frequency echosounding has many advantages, including

3876-416: The water betwixt xvi. and xvii. yards, yard and inch ; and being well scoured thicked, milled, dressed and fully dried, shall weigh nineteen pounds the piece at the least:... As recently as 1593, the same principle is found mentioned once again ( 35 Eliz. 1 . c. 10 An act for the reformation of sundry abuses in clothes, called Devonshire kerjies [ sic ] or dozens, according to a proclamation of

3944-568: The yard and handful to evade high taxes on cloth (the extra handful being essentially a black-market transaction). Enforcement efforts resulted in cloth merchants switching over to the yard and inch, at which point the government gave up and made the yard and inch official. In 1552, the yard and inch for cloth measurement was again sanctioned in law ( 5 & 6 Edw. 6 . c. 6. An Act for the true making of Woolen Cloth. ) XIV. And that all and every Broad Cloth and Clothes called Taunton Clothes , Bridgwaters , and other Clothes which shall be made after

4012-426: The yard of three English feet from pacing; others from the ell or cubit; and still others from Henry I 's arm standard ( see below ). Based on the etymology of the other "yard" , some suggest it originally derived from the girth of a person's waist, while others believe it originated as a cubic measure . One official British report writes: The standard of measure has always been taken either from some part of

4080-412: The yard, but not specific to cloth measurement: two yards are a fathom , a quarter of a yard (when not referring to cloth) is a span . Echo sounding Echo sounding or depth sounding is the use of sonar for ranging , normally to determine the depth of water ( bathymetry ). It involves transmitting acoustic waves into water and recording the time interval between emission and return of

4148-560: Was among the most conscientious and trustworthy medieval historians. The French " king's foot " was supposed to have derived from Charlemagne , and the English kings subsequently repeatedly intervened to impose shorter units with the aim of increasing tax revenue. The earliest surviving definition of this shorter unit appears in the Act on the Composition of Yards and Perches , one of the statutes of uncertain date tentatively dated to

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4216-487: Was made from the Royal Society's standard and was deposited with the clerk of the House of Commons ; it was divided into feet, one of the feet into inches, and one of the inches into tenths. A copy of it, but with upright cheeks between which other measuring rods could be placed, was made for the Exchequer for commercial use. Following Royal Society investigations by John Playfair , Hyde Wollaston and John Warner in 1814

4284-423: Was made of Baily's metal No. 4 consisting of 16 parts copper, 2 + 1 ⁄ 2 parts tin, and 1 part zinc. It was 38 inches long and 1 inch square. The Weights and Measures Act 1855 granted official recognition to the new standards. Between 1845 and 1855 forty yard standards were constructed, one of which was selected as the new Imperial standard. Four others, known as 'parliamentary copies', were distributed to

4352-404: Was the fathom , an instrument used for determining water depth is sometimes called a fathometer . Most charted ocean depths are based on an average or standard sound speed. Where greater accuracy is required, average and even seasonal standards may be applied to ocean regions. For high accuracy depths, usually restricted to special purpose or scientific surveys, a sensor may be lowered to measure

4420-623: Was the toise in France . In Hungary the square fathom (" négyszögöl ") is still in use as an unofficial measure of land area, primarily for small lots suitable for construction. Yard The yard (symbol: yd ) is an English unit of length in both the British imperial and US customary systems of measurement equalling 3  feet or 36  inches . Since 1959 it has been by international agreement standardized as exactly 0.9144  meter . A distance of 1,760 yards

4488-404: Was upset and rose to the surface. A shot , one of the forged lengths of chain joined by shackles to form an anchor cable, was usually 15 fathoms (90 ft; 27 m). A shackle , a length of cable or chain equal to 12 + 1 ⁄ 2 fathoms (75 ft; 22.9 m). In 1949, the British navy redefined the shackle to be 15 fathoms (90 ft; 27 m). The Finnish fathom ( syli )

4556-600: Was used in Britain and the United States. No conflict between the definitions existed in practice, since depths on imperial nautical charts were indicated in feet if less than 30 feet (9.1 m) and in fathoms for depths greater than that. Until the 19th century in England, the length of the fathom was more variable: from 5 + 1 ⁄ 2  feet on merchant vessels to either 5 or 7 feet (1.5 or 2.1 m) on fishing vessels (from 1.7 to 1.5 or 2.1 m). At one time,

4624-474: Was usually provided in bundles of 300 fathoms. A single 50-fathom (300 ft; 91 m) skein of this rope was referred to as a line . Especially in Pacific coast fisheries the setline was composed of units called skates , each consisting of several hundred fathoms of groundline, with gangions and hooks attached. A tuck seine or tuck net about 70 fathoms (420 ft; 130 m) long, and very deep in

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