The history of anchors
Despite being iconic for the shape we know today, the first anchors were simply rocks and many examples of these basic anchors have been found dating back to the bronze age. Today there are many different types and designs of anchor, however, the basic function, to connect a vessel to the seafloor to prevent it drifting because of ocean currents or wind, is the same.
Baskets of stones were used by the Ancient Greeks, and pre-European Maori waka (canoe), used hollowed out stones tied with flax ropes as anchors. Rocks are still used as anchors today as the basis for many permanent moorings. Rocks are only really suitable for permanent moorings as it is very hard to transport a rock that weighs enough to stop a ship from drifting, on the ship itself. This equation is similar to the thrust to weight ratio that rocket scientists grapple with.
Over time, anchor design has developed in tandem with advances in metallurgy and woodworking to create more efficient and effective anchors. The early 1800s saw significant advances in anchor design, which led to the shame we recognise today.
How do anchors work?
Anchors work by using a combination of their sheer mass and hooking onto the seafloor to secure them in place. Larger anchors, for instance, those on cruise ships, which can weigh in excess of 25 tonnes and rely mainly on their mass, whilst anchors on smaller boats have design features such as a fluke that hooks onto rocks or embed themselves in the soft sea bed. A fluke is the triangular-like part at either end of the curved crown, as seen in the diagram below.
Once the anchor has been dropped, the process of anchoring is more about horizontal force and the way that the anchor hooks into the sea bed. There also needs to be enough slack in the chain to stop the vessel from moving the anchor around.
As the excellent video below explains, the huge modern ships we have today rely on the chain that is attached to the anchor as much as the anchor itself.
The area of the seabed that the anchor is dropped into can have a significant bearing on the holding power of the anchor and is known as ‘holding ground’. Hard sand is very good, whereas shell is so poor that the ship is totally reliant on the weight of the anchor to keep it in place.
Larger vessels will often have more than one anchor and these can be different designs and weights. Ships only anchor in water shallow enough that the anchor will reach the bottom; in open water there is no danger of the vessel floating into anything, so no need to secure it in place.
As well as anchors that connect to the seafloor, there are what’s known as ‘drogues’, which are drag devices that use the weight of water to slow a ship.
The anatomy of an anchor
Although there are many different types of anchors, they all share the same basic purpose and thus many elements of their anatomy are the same.
All versions of anchors include a shaft and some kind of variation of ‘arms’, however all modern anchor designs are ‘stockless’. The main advantage of a stockless design is that it is much easier to store onboard a ship.
Anchor design
The design of anchors has come a long way since the Ancient Greeks were using baskets of rocks and wood with lead, and today there are anchors of many types and sizes. Iron is still a very popular material in the production of anchors and the proliferation of iron ushered in several improvements in anchor design and construction during the previous 2 millenniums.
Most modern anchors are stockless, which means they are slightly different from the typical image of an anchor that we all have in our heads. The stock has become less prevalent as it makes the anchor cumbersome and hard to store on ship without adding enough in the way of staying power to make these drawbacks acceptable.
Admiralty anchor
Probably the most recognisable anchor design, the admiralty anchor has several variations. However, it has remained basically unchanged for centuries. Its basic design consists of a shaft, two arms, and a stock with the stock being perpendicular to the arms. Later designs replaced the wooden stock for an iron one and innovations consisted mainly of adjustments to the proportions of the anchor.
Trotman Anchors
The Trotman anchor is considered the most successful alteration to the design of the admiralty anchor and it was intended to alleviate the issues of the anchor being lifted from the sea floor in the event of strong winds and currents.
The design features a pivot in the centre of the crown, allowing the shaft to swing until it folds up to the arm that was not embedded in the seafloor.
Stockless anchors
The stockless anchor was patented in England in 1821 and was quickly adopted by the majority of seafarers and shipyards. There are many variations of stockless anchor however all consist of heavy flukes that are connected, by a pivot, to a shaft. Gripping palms are cast into the crown of the anchor, these projections drag on the bottom forcing the flukes in the ground.
Halls anchors
The Halls anchor is a stockless bow anchor with a holding power of 3-4 times its weight. The advantage of the Halls anchor is that it can be raised and the flukes rest against the side of the hull or a recess in the hull of the ship.
Future anchor design
Innovation and improvement in anchor design has continued into the 21st century. As recently as the 2000s, new anchor designs have been introduced. The Rocna, developed by experienced sailor Peter Smith, includes a self-righting roll bar and is a general-purpose anchor design for smaller boats.
Famous Anchors
One of the most famous anchors of all time was on one of the most famous ships of all time: the Titanic.
The Titanic had two anchors, a side and central anchor and the central anchor was, at the time of its manufacture and for some time afterwards, the largest hand forged anchor in the world.
It was a Halls anchor design and was forged from steel, manufactured by 3 companies in Newcastle, Halesowen, and Dudley in the United Kingdom.
When completed, the centre anchor weighed almost 8 tonnes and was 15 feet in length.
The company who produced the shank for the anchor, Somers, based in Halesowen, still manufactures anchor shanks, as well as other marine parts, for commercial and naval vessels. They are the 10th oldest family-run company in the UK and can manufacture parts from 1kg to 80 tonnes.
Do ships still have anchors?
Yes, and some of them are huge. Whilst some modern ships have the capability to “dynamically position”, using propulsion and thrusters instead of anchors, this uses fuel and releases more emissions than dropping an anchor, so this is often still the best option. The basic purpose of the anchor has not changed and is still a necessity.
How much do anchors cost?
Obviously, this depends a lot on size; small commercial anchors can start from as little as £50, however the large anchors required for gigantic modern cruise ships are much more expensive.
To make new these anchors can costs hundreds of thousands of pounds and even have a salvage value of upwards of $500,000
Anchors in popular culture
Although air travel has taken over as the primary method of international travel, depictions of anchors are everywhere and their initial popularity as a symbol can be attributed to their use in Christian symbolism.
Anchors in Christian imagery have been discovered in ancient catacombs and they were mentioned in the New Testament: ‘’This hope we have as an anchor of the soul, a hope both sure and steadfast and one which enters within the veil,’’ Hebrews 6:19.
The anchor is also the symbol or St. Clement of Rome, who was killed by being tied to an anchor and thrown into the sea.
Early Christians used the image of an anchor as a hidden way of representing the cross.
Anchors on headstones
When depicted on a headstone, an anchor means one of two things. It either communicates that the deceased was a Seafarer or that they were steadfast in faith. If the former, the deceased will be named as captain and sometimes the name of the ship will also be included on the gravestone.
Graves with anchors are more common close to the coast and anchors found on graves inland are more likely to be associated with faith.
Images courtesy of headstonesymbols.co.uk
Anchors and tattoos
As the history of tattoos is closely associated with the profession of sailing, it’s no surprise that anchor tattoos are both very popular and have a long history in European body art. It was a sailor, Captain James Cook, who first observed the practice of tattooing as he sailed between pacific islands and his crew quickly adopted the practice.
As sailing is both a dangerous and unpredictable occupation there is much folklore, legend, and superstition that goes along with it. Tattoos on sailors could help to identify experience and seniority and many of the symbols used were intended to serve as amulets to protect against misfortunes common at sea.
Other symbols such as compasses, nautical stars, masts, and entire ships are also common, however, as the anchor was also used in Christian iconography as far back as 100-400 AD, they have special meaning and are particularly prolific.
Anchors in Jewellery
As there is strong meaning and symbolism attached to anchors, they are popular in jewellery too. There are examples of anchors being made from materials such as gold and silver as early as the 15th century and many of these early pieces are heavily associated with the Christian faith, with some featuring depictions of Christ on the cross. These were often part of a rosary, like the example to the left dated 1665 and of German origin.
Almost all depictions of anchors in jewellery are 2D representations, with the stock being parallel to the arms of the anchor unline in real life where they are perpendicular. Ropes are often featured in the designs, wrapping around the shank and arms.
Some of the earliest examples of anchors in jewellery are from the Vikings. These date back to the 8th century and are made from Bronze.
In the 19th century, jewellers began to embellish anchors with gemstones like diamonds and experiment with materials such as enamel. Diamonds especially become more available in the early part of the century and there is no specific meaning associated with anchors and any specific gemstone.
Image from Christies
Anchor hallmark
The Anchor is the mark of the Birmingham assay office and all items hallmarked there bear this logo. A modern hallmark consists of compulsory marks and one discretionary mark. The decision to designate the Anchor as the symbol of the Birmingham assay office came about as Matthew Boulton, who founded the Birmingham Assay office stayed in the Crown and Anchor Tavern on the Strand, whilst in London.