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71-468: On Monday, November 22, 2010, the Soccer Centre's expansions (known most commonly as "the bubble") collapsed for the second time in two years. According to Perry Logan, the general manager at the time , the collapse was most likely caused by a supporting anchor collapsing before carving a rip in the material. Nobody was inside the bubble and therefore no one was injured in the incident. In 2014,

142-545: A 1933 design patented in the UK by mathematician Geoffrey Ingram Taylor . Plough anchors stow conveniently in a roller at the bow, and have been popular with cruising sailors and private boaters. Ploughs can be moderately good in all types of seafloor, though not exceptional in any. Contrary to popular belief, the CQR's hinged shank is not to allow the anchor to turn with direction changes rather than breaking out, but actually to prevent

213-673: A 1989 US Naval Sea Systems Command (NAVSEA) test and in an August 2014 holding power test that was conducted in the soft mud bottoms of the Chesapeake Bay. This claw-shaped anchor was designed by Peter Bruce from Scotland in the 1970s. Bruce gained his early reputation from the production of large-scale commercial anchors for ships and fixed installations such as oil rigs. It was later scaled down for small boats, and copies of this popular design abound. The Bruce and its copies, known generically as "claw type anchors", have been adopted on smaller boats (partly because they stow easily on

284-560: A bow roller) but they are most effective in larger sizes. Claw anchors are quite popular on charter fleets as they have a high chance to set on the first try in many bottoms. They have the reputation of not breaking out with tide or wind changes, instead slowly turning in the bottom to align with the force. Bruce anchors can have difficulty penetrating weedy bottoms and grass. They offer a fairly low holding-power-to-weight ratio and generally have to be oversized to compete with newer types. Three time circumnavigator German Rolf Kaczirek invented

355-535: A cause, who composed The Causes , Callimachus. Ancient sources describe Callimachus's poem Ibis — which does not survive — as a polemic and some of them identified Apollonius as the target. These references conjure up images of a sensational literary feud between the two figures. Such a feud is consistent with what we know of Callimachus's taste for scholarly controversy and it might even explain why Apollonius departed for Rhodes. Thus there arises "a romantic vision of scholarly warfare in which Apollonius

426-439: A concave fluke shaped like the blade of a shovel, with a shank attached parallel to the fluke, and the load applied toward the digging end. It is designed to dig into the bottom like a shovel, and dig deeper as more pressure is applied. The common challenge with all the scoop type anchors is that they set so well, they can be difficult to weigh. These are used where the vessel is permanently or semi-permanently sited, for example in

497-486: A deadweight anchor over a mushroom is that if it does drag, it continues to provide its original holding force. The disadvantage of using deadweight anchors in conditions where a mushroom anchor could be used is that it needs to be around ten times the weight of the equivalent mushroom anchor. Auger anchors can be used to anchor permanent moorings, floating docks, fish farms, etc. These anchors, which have one or more slightly pitched self-drilling threads, must be screwed into

568-575: A feud between Callimachus and Apollonius. The evidence partly rests on an elegiac epigram in the Palatine Anthology , attributed to "Apollonius the grammarian". It blames Callimachus for some unstated offense and mocks both him and his most famous poem, the Aetia (" Causes "): Καλλίμαχος, τὸ κάθαρμα, τὸ παίγνιον, ὁ ξυλινὸς νοῦς, αἴτιος, ὁ γράψας Αἴτια Καλλίμαχος. Callimachus, that discard, that plaything, that mahogany noggin, Himself

639-404: A fluked anchor of this type, made of iron, which would have had a wooden stock mounted perpendicular to the shank and flukes to make the flukes contact the bottom at a suitable angle to hook or penetrate. The Admiralty Pattern anchor, or simply "Admiralty", also known as a "Fisherman", consists of a central shank with a ring or shackle for attaching the rode (the rope, chain, or cable connecting

710-684: A hook. If there is much current, or if the vessel is moving while dropping the anchor, it may "kite" or "skate" over the bottom due to the large fluke area acting as a sail or wing. The FOB HP anchor designed in Brittany in the 1970s is a Danforth variant designed to give increased holding through its use of rounded flukes setting at a 30° angle. The Fortress is an American aluminum alloy Danforth variant that can be disassembled for storage and it features an adjustable 32° and 45° shank/fluke angle to improve holding capability in common sea bottoms such as hard sand and soft mud. This anchor performed well in

781-510: A large rock as the primary element of their design. However, using pure weight to resist the forces of a storm works well only as a permanent mooring; a large enough rock would be nearly impossible to move to a new location. The ancient Greeks used baskets of stones, large sacks filled with sand, and wooden logs filled with lead. According to Apollonius Rhodius and Stephen of Byzantium , anchors were formed of stone, and Athenaeus states that they were also sometimes made of wood. Such anchors held

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852-418: A lightweight anchor for seaplanes, this design consists of two plough-like blades mounted to a shank, with a folding stock crossing through the crown of the anchor. Many manufacturers produce a plough-type anchor, so-named after its resemblance to an agricultural plough . All such anchors are copied from the original CQR ( Coastal Quick Release , or Clyde Quick Release , later rebranded as 'secure' by Lewmar),

923-461: A load that is entirely horizontal, whilst an anchor rode made only of rope will never achieve a strictly horizontal pull. Apollonius of Rhodes Apollonius of Rhodes ( Ancient Greek : Ἀπολλώνιος Ῥόδιος Apollṓnios Rhódios ; Latin : Apollonius Rhodius ; fl. first half of 3rd century BC) was an ancient Greek author , best known for the Argonautica , an epic poem about Jason and

994-470: A much higher fluke area to weight ratio than its predecessor. The designers also eliminated the sometimes troublesome hinge. It is a plough anchor with a rigid, arched shank. It is described as self-launching because it can be dropped from a bow roller simply by paying out the rode, without manual assistance. This is an oft copied design with the European Brake and Australian Sarca Excel being two of

1065-411: A prolific author. Apollonius set out to integrate new understandings of the physical world with the mythical geography of tradition and his Argonautica was, in that sense, a didactic epic on geography, again without detracting from its merits as poetry. The Argonautica differs in some respects from traditional or Homeric Greek epic, though Apollonius certainly used Homer as a model. The Argonautica

1136-439: A renaissance of interest in the poem and an awareness of its qualities: numerous scholarly studies are published regularly, its influence on later poets like Virgil is now well recognised, and any account of the history of epic poetry now routinely includes substantial attention to Apollonius. A handful of fragments are all that survive of his other work, mostly ktiseis ( κτίσεις ) or 'foundation-poems', apparently dealing with

1207-413: A silt or mud bottom, since they rely upon suction and cohesion of the bottom material, which rocky or coarse sand bottoms lack. The holding power of this anchor is at best about twice its weight until it becomes buried, when it can be as much as ten times its weight. They are available in sizes from about 5 kg up to several tons. A deadweight is an anchor that relies solely on being a heavy weight. It

1278-511: A support tug and pennant/pendant wire. Some examples are the Stevin range supplied by Vrijhof Ankers. Large plate anchors such as the Stevmanta are used for permanent moorings. The elements of anchoring gear include the anchor, the cable (also called a rode ), the method of attaching the two together, the method of attaching the cable to the ship, charts, and a method of learning the depth of

1349-430: A trip line from the crown, it is impossible to retrieve. Designed by yacht designer L. Francis Herreshoff , this is essentially the same pattern as an admiralty anchor, albeit with small diamond-shaped flukes or palms. The novelty of the design lay in the means by which it could be broken down into three pieces for stowage. In use, it still presents all the issues of the admiralty pattern anchor. Originally designed as

1420-404: A unique time in history. The most reliable information we have about ancient poets is largely drawn from their own works. Unfortunately, Apollonius of Rhodes reveals nothing about himself. Most of the biographical material comes from four sources: two are texts entitled Life of Apollonius found in the scholia on his work ( Vitae A and B); a third is an entry in the 10th-century encyclopaedia

1491-489: A variety of other non-mass means of getting a grip on the bottom. One method of building a mooring is to use three or more conventional anchors laid out with short lengths of chain attached to a swivel, so no matter which direction the vessel moves, one or more anchors are aligned to resist the force. The mushroom anchor is suitable where the seabed is composed of silt or fine sand. It was invented by Robert Stevenson , for use by an 82-ton converted fishing boat, Pharos , which

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1562-480: Is driven into the seabed. Permanent anchors come in a wide range of types and have no standard form. A slab of rock with an iron staple in it to attach a chain to would serve the purpose, as would any dense object of appropriate weight (for instance, an engine block ). Modern moorings may be anchored by augers , which look and act like oversized screws drilled into the seabed, or by barbed metal beams pounded in (or even driven in with explosives) like pilings, or by

1633-439: Is a drag device, not in contact with the seabed, used to minimise drift of a vessel relative to the water. A drogue is a drag device used to slow or help steer a vessel running before a storm in a following or overtaking sea, or when crossing a bar in a breaking sea. Anchors achieve holding power either by "hooking" into the seabed , or weight, or a combination of the two. The weight of the anchor chain can be more than that of

1704-432: Is a great tendency of the rode to foul the anchor as the vessel swings due to wind or current shifts. When this happens, the anchor may be pulled out of the bottom, and in some cases may need to be hauled up to be re-set. In the mid-19th century, numerous modifications were attempted to alleviate these problems, as well as improve holding power, including one-armed mooring anchors. The most successful of these patent anchors ,

1775-399: Is also considered to be one of the period's most important authors on geography, though approaching the subject differently from Eratosthenes , his successor at the library and a radical critic of Homer's geography. It was a time when the accumulation of scientific knowledge was enabling advances in geographical studies, as represented by the activities of Timosthenes , a Ptolemaic admiral and

1846-408: Is generally not compact and it may be awkward to stow unless a collapsing model is used. Grapnels rarely have enough fluke area to develop much hold in sand, clay, or mud. It is not unknown for the anchor to foul on its own rode, or to foul the tines with refuse from the bottom, preventing it from digging in. On the other hand, it is quite possible for this anchor to find such a good hook that, without

1917-508: Is not suited to rodes because it floats and is much weaker than nylon, being barely stronger than natural fibres. Some grades of polypropylene break down in sunlight and become hard, weak, and unpleasant to handle. Natural fibres such as manila or hemp are still used in developing nations but absorb a lot of water, are relatively weak, and rot, although they do give good handling grip and are often relatively cheap. Ropes that have little or no elasticity are not suitable as anchor rodes. Elasticity

1988-441: Is partly a function of the fibre material and partly of the rope structure. All anchors should have chain at least equal to the boat's length. Some skippers prefer an all chain warp for greater security on coral or sharp edged rock bottoms. The chain should be shackled to the warp through a steel eye or spliced to the chain using a chain splice. The shackle pin should be securely wired or moused. Either galvanized or stainless steel

2059-508: Is shorter than Homer's epics, with four books totalling fewer than 6000 lines, while the Iliad runs to more than 16,000. Apollonius may have been influenced here by Callimachus's brevity, or by Aristotle ’s demand for "poems on a smaller scale than the old epics, and answering in length to the group of tragedies presented at a single sitting" (the Poetics ). Apollonius' epic also differs from

2130-416: Is suitable for eyes and shackles, galvanised steel being the stronger of the two. Some skippers prefer to add a swivel to the rode. There is a school of thought that says these should not be connected to the anchor itself, but should be somewhere in the chain. However, most skippers connect the swivel directly to the anchor. Scope is the ratio of length of the rode to the depth of the water measured from

2201-532: Is the home venue for sports tournaments such as Jumpstart and the Canada Day lacrosse tournament. The Soccer Centre is located in the Southeast sector of Calgary , and the office is open on weekdays from 8:30 AM to 3:30 PM. There is also a lounge and sandwich shop. Anchor An anchor is a device, normally made of metal , used to secure a vessel to the bed of a body of water to prevent

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2272-402: Is usually just a large block of concrete or stone at the end of the chain. Its holding power is defined by its weight underwater (i.e., taking its buoyancy into account) regardless of the type of seabed, although suction can increase this if it becomes buried. Consequently, deadweight anchors are used where mushroom anchors are unsuitable, for example in rock, gravel or coarse sand. An advantage of

2343-521: The Suda ; and fourthly a 2nd-century BCE papyrus, P.Oxy. 1241, which provides names of several heads of the Library of Alexandria . Other scraps can be gleaned from miscellaneous texts. The reports from all the above sources however are scanty and often self-contradictory. Ancient biographies often represent famous poets as going into exile to escape their ungrateful fellow citizens. Thus for example Homer

2414-476: The Argonautica in such fine style at Rhodes that he was able to return to Alexandria in triumph, where he was rewarded with a post in the library and finally a place in the cemetery next to Callimachus. These stories were probably invented to account for the existence of a second edition of Argonautica , indicated by variant readings in ancient manuscripts. Until recently modern scholarship has made much of

2485-585: The Argonauts and their quest for the Golden Fleece . The poem is one of the few extant examples of the epic genre and it was both innovative and influential, providing Ptolemaic Egypt with a "cultural mnemonic" or national "archive of images", and offering the Latin poets Virgil and Gaius Valerius Flaccus a model for their own epics. His other poems, which survive only in small fragments, concerned

2556-583: The Bügel Anker in the 1980s. Kaczirek wanted an anchor that was self-righting without necessitating a ballasted tip. Instead, he added a roll bar and switched out the plough share for a flat blade design. As none of the innovations of this anchor were patented, copies of it abound. Alain Poiraud of France introduced the scoop type anchor in 1996. Similar in design to the Bügel anchor, Poiraud's design features

2627-528: The City of Calgary built a permanent second building (the Annex) to replace the previous structure (the "bubble"). The Annex houses four indoor soccer fields. The Calgary Soccer Centre also supports many other sports other than indoor and outdoor soccer, some of which would include field hockey , softball , football , lacrosse , lawn bowling , rugby football , and simply jogging, walking or running. The CSC also

2698-468: The Trotman Anchor, introduced a pivot at the centre of the crown where the arms join the shank, allowing the "idle" upper arm to fold against the shank. When deployed the lower arm may fold against the shank tilting the tip of the fluke upwards, so each fluke has a tripping palm at its base, to hook on the bottom as the folded arm drags along the seabed, which unfolds the downward oriented arm until

2769-427: The anchor and is critical to proper holding. Permanent moorings use large masses (commonly a block or slab of concrete) resting on the seabed. Semi-permanent mooring anchors (such as mushroom anchors ) and large ship's anchors derive a significant portion of their holding power from their weight, while also hooking or embedding in the bottom. Modern anchors for smaller vessels have metal flukes that hook on to rocks on

2840-503: The anchor is a set of tripping palms, projections that drag on the bottom, forcing the main flukes to dig in. Until the mid-20th century, anchors for smaller vessels were either scaled-down versions of admiralty anchors, or simple grapnels . As new designs with greater holding-power-to-weight ratios were sought, a great variety of anchor designs have emerged. Many of these designs are still under patent, and other types are best known by their original trademarked names. A traditional design,

2911-442: The anchor to the vessel is usually made up of chain, rope, or a combination of those. Large ships use only chain rode. Smaller craft might use a rope/chain combination or an all chain rode. All rodes should have some chain; chain is heavy but it resists abrasion from coral, sharp rocks, or shellfish beds, whereas a rope warp is susceptible to abrasion and can fail in a short time when stretched against an abrasive surface. The weight of

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2982-516: The anchor. Before dropping the anchor, the fishing process is reversed, and the anchor is dropped from the end of the cathead. The stockless anchor, patented in England in 1821, represented the first significant departure in anchor design in centuries. Although their holding- power-to-weight ratio is significantly lower than admiralty pattern anchors, their ease of handling and stowage aboard large ships led to almost universal adoption. In contrast to

3053-477: The beginnings or foundations of cities, such as Alexandria and Cnidus places of interest to the Ptolemies, whom he served as a scholar and librarian at the Library of Alexandria . A literary dispute with Callimachus , another Alexandrian librarian/poet, is a topic much discussed by modern scholars since it is thought to give some insight into their poetry, although there is very little evidence that there ever

3124-716: The bottom or bury themselves in soft seabed. The vessel is attached to the anchor by the rode (also called a cable or a warp ). It can be made of rope, chain or a combination of rope and chain. The ratio of the length of rode to the water depth is known as the scope (see below). Holding ground is the area of sea floor that holds an anchor, and thus the attached ship or boat. Different types of anchor are designed to hold in different types of holding ground. Some bottom materials hold better than others; for instance, hard sand holds well, shell holds poorly. Holding ground may be fouled with obstacles. An anchorage location may be chosen for its holding ground. In poor holding ground, only

3195-447: The bottom type). Tripping palms at the crown act to tip the flukes into the seabed. The design is a burying variety, and once well set can develop high resistance. Its lightweight and compact flat design make it easy to retrieve and relatively easy to store; some anchor rollers and hawsepipes can accommodate a fluke-style anchor. A Danforth does not usually penetrate or hold in gravel or weeds. In boulders and coral it may hold by acting as

3266-400: The bottom, and this absorbs shock loads until the chain is straight, at which point the full load is taken by the anchor. Additional dissipation of shock loads can be achieved by fitting a snubber between the chain and a bollard or cleat on deck. This also reduces shock loads on the deck fittings, and the vessel usually lies more comfortably and quietly. Being strong and elastic, nylon rope is

3337-460: The bottom. The Admiralty Anchor is an entirely independent reinvention of a classical design, as seen in one of the Nemi ship anchors. This basic design remained unchanged for centuries, with the most significant changes being to the overall proportions, and a move from stocks made of wood to iron stocks in the late 1830s and early 1840s. Since one fluke always protrudes up from the set anchor, there

3408-410: The case of lightvessels or channel marker buoys . The anchor needs to hold the vessel in all weathers, including the most severe storm , but needs to be lifted only occasionally, at most – for example, only if the vessel is to be towed into port for maintenance. An alternative to using an anchor under these circumstances, especially if the anchor need never be lifted at all, may be to use a pile that

3479-454: The chain also helps keep the direction of pull on the anchor closer to horizontal, which improves holding, and absorbs part of snubbing loads. Where weight is not an issue, a heavier chain provides better holding by forming a catenary curve through the water and resting as much of its length on the bottom as would not be lifted by tension of the mooring load. Any changes to the tension are accommodated by additional chain being lifted or settling on

3550-513: The craft from drifting due to wind or current . The word derives from Latin ancora , which itself comes from the Greek ἄγκυρα ( ankȳra ). Anchors can either be temporary or permanent. Permanent anchors are used in the creation of a mooring , and are rarely moved; a specialist service is normally needed to move or maintain them. Vessels carry one or more temporary anchors, which may be of different designs and weights. A sea anchor

3621-464: The elaborate stowage procedures for earlier anchors, stockless anchors are simply hauled up until they rest with the shank inside the hawsepipes, and the flukes against the hull (or inside a recess in the hull called the Anchor Box). While there are numerous variations, stockless anchors consist of a set of heavy flukes connected by a pivot or ball and socket joint to a shank. Cast into the crown of

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3692-539: The epic, following the Hellenistic trend to allegorise and rationalise religion. Heterosexual loves such as Jason's are more emphasized than homosexual loves such as that of Heracles and Hylas , another trend in Hellenistic literature. Many critics regard the love of Medea and Jason in the third book as the best written and most memorable episode. Opinions on the poem have changed over time. Some critics in antiquity considered it mediocre. Recent criticism has seen

3763-967: The feud, but most scholars of Hellenistic literature now believe it has been enormously sensationalised, if it happened at all. Apollonius was among the foremost Homeric scholars in the Alexandrian period. He wrote the period's first scholarly monograph on Homer, critical of the editions of the Iliad and Odyssey published by Zenodotus , his predecessor as head of the Library of Alexandria. Argonautica seems to have been written partly as an experimental means of communicating his own researches into Homer's poetry and to address philosophical themes in poetry. It has even been called "a kind of poetic dictionary of Homer", without at all detracting from its merits as poetry. He has been credited with scholarly prose works on Archilochus and on problems in Hesiod . He

3834-490: The grapnel is merely a shank (no stock) with four or more tines, also known as a drag . It has a benefit in that, no matter how it reaches the bottom, one or more tines are aimed to set. In coral, or rock, it is often able to set quickly by hooking into the structure, but may be more difficult to retrieve. A grapnel is often quite light, and may have additional uses as a tool to recover gear lost overboard. Its weight also makes it relatively easy to move and carry, however its shape

3905-419: The highest point (usually the anchor roller or bow chock) to the seabed, making allowance for the highest expected tide. When making this ratio large enough, one can ensure that the pull on the anchor is as horizontal as possible. This will make it unlikely for the anchor to break out of the bottom and drag, if it was properly embedded in the seabed to begin with. When deploying chain, a large enough scope leads to

3976-406: The location of potential dangers, as well as being useful in estimating the effects of weather and tide in the anchorage, is essential in choosing a good place to drop the hook. One can get by without referring to charts, but they are an important tool and a part of good anchoring gear, and a skilled mariner would not choose to anchor without them. The anchor rode (or "cable" or "warp") that connects

4047-496: The more notable ones. Although it is a plough type anchor, it sets and holds reasonably well in hard bottoms. American Richard Danforth invented the Danforth Anchor in the 1940s for use aboard landing craft . It uses a stock at the crown to which two large flat triangular flukes are attached. The stock is hinged so the flukes can orient toward the bottom (and on some designs may be adjusted for an optimal angle depending on

4118-412: The more traditional epic in its weaker, more human protagonist Jason and in its many digressions into local custom, aetiology , and other popular subjects of Hellenistic poetry. Apollonius also chooses the less shocking versions of some myths, having Medea , for example, merely watch the murder of Apsyrtus instead of murdering him herself. The gods are relatively distant and inactive throughout much of

4189-448: The most suitable as an anchor rode. Polyester (terylene) is stronger but less elastic than nylon. Both materials sink, so they avoid fouling other craft in crowded anchorages and do not absorb much water. Neither breaks down quickly in sunlight. Elasticity helps absorb shock loading, but causes faster abrasive wear when the rope stretches over an abrasive surface, like a coral bottom or a poorly designed chock. Polypropylene ("polyprop")

4260-544: The seabed with the use of a tool, so require access to the bottom, either at low tide or by use of a diver. Hence they can be difficult to install in deep water without special equipment. Weight for weight, augers have a higher holding than other permanent designs, and so can be cheap and relatively easily installed, although difficult to set in extremely soft mud. There is a need in the oil-and-gas industry to resist large anchoring forces when laying pipelines and for drilling vessels. These anchors are installed and removed using

4331-410: The seafloor. By contrast, modern efficient anchors tend to be "scoop" types that dig ever deeper. The Delta anchor was derived from the CQR. It was patented by Philip McCarron, James Stewart, and Gordon Lyall of British marine manufacturer Simpson-Lawrence Ltd in 1992. It was designed as an advance over the anchors used for floating systems such as oil rigs. It retains the weighted tip of the CQR but has

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4402-487: The shank's weight from disrupting the fluke's orientation while setting. The hinge can wear out and may trap a sailor's fingers. Some later plough anchors have a rigid shank, such as the Lewmar's "Delta". A plough anchor has a fundamental flaw: like its namesake, the agricultural plough, it digs in but then tends to break out back to the surface. Plough anchors sometimes have difficulty setting at all, and instead skip across

4473-403: The ship and the anchor). At the other end of the shank there are two arms, carrying the flukes, while the stock is mounted to the shackle end, at ninety degrees to the arms. When the anchor lands on the bottom, it generally falls over with the arms parallel to the seabed. As a strain comes onto the rope, the stock digs into the bottom, canting the anchor until one of the flukes catches and digs into

4544-420: The tip of the fluke can engage the bottom. Handling and storage of these anchors requires special equipment and procedures. Once the anchor is hauled up to the hawsepipe , the ring end is hoisted up to the end of a timber projecting from the bow known as the cathead . The crown of the anchor is then hauled up with a heavy tackle until one fluke can be hooked over the rail. This is known as "catting and fishing"

4615-469: The vessel merely by their weight and by their friction along the bottom. Iron was afterwards introduced for the construction of anchors, and an improvement was made by forming them with teeth, or "flukes", to fasten themselves into the bottom. This is the iconic anchor shape most familiar to non-sailors. This form has been used since antiquity. The Roman Nemi ships of the 1st century AD used this form. The Viking Ladby ship (probably 10th century) used

4686-641: The water. Vessels may carry a number of anchors: bower anchors are the main anchors used by a vessel and normally carried at the bow of the vessel. A kedge anchor is a light anchor used for warping an anchor , also known as kedging , or more commonly on yachts for mooring quickly or in benign conditions. A stream anchor , which is usually heavier than a kedge anchor , can be used for kedging or warping in addition to temporary mooring and restraining stern movement in tidal conditions or in waters where vessel movement needs to be restricted, such as rivers and channels. Charts are vital to good anchoring. Knowing

4757-533: The weight of an anchor and chain matters; in good holding ground, it is able to dig in, and the holding power can be significantly higher. The word "anchor" is sometimes used as British slang for the brakes on a car. The earliest anchors were probably rocks, and many rock anchors have been found dating from at least the Bronze Age . Pre-European Māori waka (canoes) used one or more hollowed stones, tied with flax ropes, as anchors. Many modern moorings still rely on

4828-453: Was finally driven out of Alexandria by a triumphant Callimachus". However, both of the Lives of Apollonius stress the friendship between the poets, the second Life even saying they were buried together; moreover Callimachus's poem Ibis is known to have been deliberately obscure and some modern scholars believe the target was never meant to be identified. There is still not a consensus about

4899-523: Was said to have left Cyme because the government there would not support him at public expense ( Vit. Herod. 13-14), Aeschylus left Athens for Sicily because Athenians valued him less than some other poets ( Vit. Aesch. ), while Euripides fled to Macedonia because of humiliation by comic poets ( Vit. Eur. ). Similarly Vitae A and B tell us that Apollonius moved to Rhodes because his work was not well received in Alexandria. According to B, he redrafted

4970-420: Was such a dispute between the two men. In fact almost nothing at all is known about Apollonius and even his connection with Rhodes is a matter for speculation. Once considered a mere imitator of Homer , and therefore a failure as a poet, his reputation has been enhanced by recent studies, with an emphasis on the special characteristics of Hellenistic poets as scholarly heirs of a long literary tradition writing at

5041-539: Was used as a lightvessel between 1807 and 1810 near to Bell Rock whilst the lighthouse was being constructed. It was equipped with a 1.5-ton example. It is shaped like an inverted mushroom, the head becoming buried in the silt. A counterweight is often provided at the other end of the shank to lay it down before it becomes buried. A mushroom anchor normally sinks in the silt to the point where it has displaced its own weight in bottom material, thus greatly increasing its holding power. These anchors are suitable only for

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