Navigators toolchest- Before charts

Navigators toolchest- Before charts

Background

Of all the tools the navigator uses the chart is his most used one and where all the position-finding data is deposited. It is the tool that describes the historic and current position of the ship.

So how did the sea chart or chart as it is called come about?

Before charts-the oral traditions

Seafarers crossed the oceans long before there were charts. The Vikings, the Pacific Islanders and the Arabs did not have charts, yet they managed to cross oceans. In the case of the Pacific Islanders, vast distances.

Essentially, they were tuned in to their maritime environment.

They were aware of prevailing winds, swells, waves. They could detect how close they were to shore by clouds on the horizon, by birds appearing around the ship. They could interpret the colour of the sea as an indicator of water depth or ocean current. Their senses were tuned to changes in wind direction and strength, so important on frail ships with limited manoeuvrability. The sound and sight of breaking waves in an otherwise regular sea warned of danger.

They were with nature and they used that knowledge to navigate.

In each case there were special conditions that affected their voyages.

The Vikings westward voyages were affected by prevailing south westerly winds that were severe in winter. Therefore, it was normal to start a voyage in the summer, overwintering in Iceland and continuing to Greenland the next summer.

The Arabs had the seasonal monsoons from the southwest and the northeast that affected their trading destinations over a year.

The Pacific islanders ventured out in the springtime or early summer to avoid the cyclone season in the southern hemisphere.

In the case of the Vikings, they were very experienced seaman crossing some of the most hostile seas in the northern hemisphere.[1]

They often missed their destination and lost ships but continued to explore the northern seas.[2]

They then passed on that knowledge to other seafarers as part of an oral tradition.

There was a distinct hierarchy of command on board ship.

“The styrimaðr had knowledge of navigation – he was able to determine the ship's distance, course and speed, and sail according to the signs provided by nature. If the styrimaðr lacked information for a voyage, or if he had to navigate in foreign waters, he hired a pilot with local knowledge who navigated and showed him the way in return for payment.

The styrimaðr had access to a kind of navigation council: the mót, which he could consult on sailing matters, such as large changes in course or in case of disciplinary punishment of the crew.”[3]

A couple of centuries after the voyages to Greenland, the voyages were recorded in the Greenland saga[4] and the saga of Erik the Red. Although detail of the lands discovered and settled is there, there is less information on the voyages.         

Early navigational tools

In addition to their intimate knowledge of their watery environment and past on information from other navigators they were knowledgeable about the sun and stars and could use them to determine direction and latitude. The Pole star and the Sun were vital celestial objects that these sailors knew. The pole star gave them a northerly direction in the northern hemisphere and when the sun reached its highest point in the sky it was either south or north depending which half of the globe you were navigating in.

The Pacific islanders were also experienced navigators that sailed between the Pacific islands only using their mental maps of the ocean and its swells.[5] In the Marshal islands they trained their mental maps with rudimentary diagrams of the islands and swells called stick charts.[6] Shell indicated islands and strands of coconut fibre represented the directions of the prevalent swells. The tradition of ocean navigation was passed down from generation to generation. Mau Piailug was one of these experienced sailors from the Caroline islands.[7]

They also had strict rank system with Captain and master navigator in charge of the canoe.[8]

The navigation of the Arab dhow also utilised simple tools. The navigator used a simple rectangular piece of wood with a string attached in its centre. It was called a kamal.[9]

The string had knots in it representing known angles of the Pole star above the horizon. Holding the string between your teeth you aligned the lower edge of the kamal with the horizon and then extended or retracted the kamal until the upper edge aligned with star. The knot closest to your teeth represented the altitude of the star, meaning latitude with the Pole star.

It is best used in lower latitudes.

They also had a master navigator called a “nakhuda”[10] who was responsible for navigation and administration, effectively the captain of the dhow.

[11]

The Vikings in higher northern latitudes also used celestial objects, particularly the sun to determine their latitude. Discovery of part of a wooden disk with notches on its perimeter in Greenland[12] led to much research that finally determined it was a “sun compass” based on observations of the suns shadow of a stick, somewhat like a sun dial. On a sunny day they could accurately measure latitude. However the sun was not always clearly visible but on hazy days they used the properties of a crystal to find the suns bearing. This was calcite crystal found in Iceland which when pointed towards the sun provides two images which through rotation of the crystal polarise into a single image indicating the suns direction.[13] Evidence of such a navigational instrument was confirmed by the discovery of one in a shipwreck from the late 1500’s.[14]

Navigating without charts continued until the 1400’s when the Chinese began to explore westward.

We will explore the emergence of sea charts in another article.

References

BBC News. ‘“Viking Sunstone” Found in Shipwreck’. Europe. 6 March 2013. https://www.bbc.com/news/world-europe-21693140.

‘Did Traditional Arab Dhows Have a Captain - Google-Søk’. Accessed 16 February 2026. https://www.google.com/search?q=did+traditional+arab+dhows+haven66B9zG8JFVLtPSE

Horte, Louise Kæmpe Henriksen-red:Marianne Juelsgård. ‘Styrimaðr’. Accessed 8 February 2026. https://www.vikingeskibsmuseet.dk/en/professions/education/knowledge-of-sailing/the-ships-crew/crewmembers-in-the-viking-age/styrimadr.

‘Portolan Chart | Maritime Navigation, Nautical Maps, Cartography | Britannica’. Accessed 8 February 2026. https://www.britannica.com/technology/portolan-chart.

Sun Compasses | Viking Archaeology. n.d. Accessed 8 March 2026. http://viking.archeurope.com/ships/navigation/sun-compasses/.

‘The Penguin Historical Atlas of the Vikings by John Haywood: 9780140513288 | PenguinRandomHouse.Com: Books’. PenguinRandomhouse.Com, n.d. Accessed 8 February 2026. https://www.penguinrandomhouse.com/books/272338/the-penguin-historical-atlas-of-the-vikings-by-john-haywood/.

‘Viking Sun Stone - Google Search’. Accessed 8 March 2026. https://www.google.com/search?q=viking+sun+stone&sca_esv=629d06c47799

 

 

 

 

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[1] ‘The Penguin Historical Atlas of the Vikings by John Haywood: 9780140513288 | PenguinRandomHouse.Com: Books’, PenguinRandomhouse.Com, n.d., accessed 8 February 2026, https://www.penguinrandomhouse.com/books/272338/the-penguin-historical-atlas-of-the-vikings-by-john-haywood/.

[2] ‘Bjarni Herjólfsson’, Wikipedia, 22 November 2025, https://en.wikipedia.org/w/index.php?title=Bjarni_Herj%C3%B3lfsson&oldid=1323627995.

[3] Louise Kæmpe Henriksen-red:Marianne Juelsgård Horte, ‘Styrimaðr’, accessed 8 February 2026, https://www.vikingeskibsmuseet.dk/en/professions/education/knowledge-of-sailing/the-ships-crew/crewmembers-in-the-viking-age/styrimadr.

[4] Wikipedia, ‘Bjarni Herjólfsson’.

[5] ‘We, the Navigators’, Wikipedia, 8 October 2025, https://en.wikipedia.org/w/index.php?title=We,_the_Navigators&oldid=1315794897.

[6] ‘Marshall Islands stick chart’, Wikipedia, 31 December 2025, https://en.wikipedia.org/w/index.php?title=Marshall_Islands_stick_chart&oldid=1330440298.

[7] ‘Mau Piailug’, Wikipedia, 14 November 2025, https://en.wikipedia.org/w/index.php?title=Mau_Piailug&oldid=1322055655.

[8]

[9]

[10] ‘Did Traditional Arab Dhows Have a Captain - Google-Søk’, accessed 16 February 2026, https://www.google.com/search?q=did+traditional+arab+dhows+have+a+captain&sca_.

[11] Sun Compasses | Viking Archaeology, n.d., accessed 8 March 2026, http://viking.archeurope.com/ships/navigation/sun-compasses/.

[12] Sun Compasses | Viking Archaeology.

[13] ‘Viking Sun Stone - Google Search’, accessed 8 March 2026, https://www.google.com/search?q=viking+sun+stone&sca_esv=629d06c477996cae&hl

[14] ‘“Viking Sunstone” Found in Shipwreck’, Europe, BBC News, 6 March 2013, https://www.bbc.com/news/world-europe-21693140.

Feeding the masses at sea

 

In contrast to my earlier article on food at sea in the 1950's here is a summary of information gleaned from a recent article in  the Economist (December 20, p32).

The largest current cruise ship is the Star of the Seas at 250000 tons she is the largest playground at sea for 7600 guests and 2350 crew.

With a dining room of 500 tables and 25 other restaurants 6000 people will eat in a 2.5 hour period The chef with his 344 other chefs and 1700 catering staff will have served and cleared up 100000 meals in one day.

This is not take away food but fresh food prepared on board ship daily, a lot of it.

A sample of the magnitude of the food on board is 25000 items of which include 15000 lobster  tails and 400 tons of bottled water. 

In one day they will serve 6800kg of protein. 

This requires large storage facilities. 210 square metres alone for frozen fish. The dry store holds 4 tons rice and 2 tons sugar and there are chilled rooms for milk, cream, butter etc.

A three week planning cycle is necessary to keep pace with the feeding habits of the passsengers.

In a buffet style environment there is also a lot of waste food that has to be dealt with. 

Some of it is burnt  to produce enough energy to powere the gigantic water slide on board.

What a world.

Food at Sea

 

Seafarers today live like kings. They have all the food requirements that you would get in a hotel or a cruise ship. Deep freezes fresh vegetables etc.

It was very different in the 1950s and 60s on board a 1920s reciprocating steam engine ship.

The primary task of the ship, of course, is to go from A to B, but production of fresh water for the boiler to run the engine's and also for consumption by the crew was very important. But if there was a lack of fresh water it was the crew that suffered. There were no refrigerators. So the production of ice was quite important to maintain not only the beer cool, but the fresh vegetables cool. To combat this we often carried fresh meat in the form of live chickens, goats, sheep, etc. They used to live in boxes aft.

So maintaining a healthy diet was quite a task for the purser.

We had to order food at every port we arrived at. So leaving the UK, winter or summer, the first port was Port Said at the northern entrance to the Suez Canal. There we took on fresh vegetables, Egyptian new potatoes and seafood. Next stop was Aden at the bottom end of the Red Sea, where we took on further fresh produce and then that got us all the way to India. Arrival in Indian ports was quite important because we had Indian crew. So as we approached the Hooghly River, for Calcutta everybody got very excited because we knew that as we came into the river and took the river pilot, a lot of local boats would arrive with beautiful prawns, seafood, fish, papaya etc. All the fresh food we had missed on the outward voyage.

It's important to note that the ships that I sailed on had white officers, white warrant officers and Indian crew. All the food was cooked by the Indian crew. So early in the morning you would see the Bandari, the cook, squatting on the afterdeck with 2 stones 1 round and a flat 1 grinding the curry paste for the days food as we ate mainly Indian food.

For breakfast, for lunch and dinner. So although you could order an English breakfast for example, one of my favourite meals for breakfast time was kedgeree. A mixture of fish, egg and rice. Very nourishing.

Lunch time could be English food, or it could be Indian food. And the evening meal was most often a mixture of Indian and/or typical English fare. When the opportunity arose the crew and the officers would fish over the side of the ship. Whether we got fish in the Red Sea, or we got fish off Newfoundland, the crew would cook and we had fresh fish for a few days. We tried to keep a supply of fresh fish as much as possible. It was not always easy. In the Red Sea the problem was that sharks often took the fish off the hook before you got it on board. It was not unusual to land only the head of a fish. Very frustrating!

The opposite occurred off the Newfoundland coast where the sheer volume of large halibut often made it very difficult to haul the fish onboard ship.

Keeping healthy especially in tropical areas on ships without air conditioning was not easy. Once past Suez we sewed hammock for ourselves so we could sleep on deck as it was impossible to sleep in the cabins.

Weekly salt tablets and lime juice were mandatory with the scarcity of fresh vegetables and fruit.

Brocklebansk was a liner shipping company providing a scheduled service between Europe and India. As such we often carried a few passengers, and mealtime was always a social event for those not watchkeeping.

Each meal was a formal affair with silver service and waiters for all our meals. We had to dress up in our best uniforms, and the junior officers had their own table. However as a new apprentice you sat with the captain's table for a short while, but after that you're on the junior officer’s table.

When in port the meals were completely different because we kept watches, cargo watches and we used to eat breakfast at 2:00 in the morning. The port we're in often determined what sort of food we got, so in the Indian coast we got Indian food. On the American course, we've got American food.

However, some traditions were important. Christmas for example, whether we were in tropical area or whether we are in the colder climates in our blue uniforms rather than a tropical uniform we always had a English Christmas meal. That meant a bird and Christmas pudding. Plus, of course, funny hats.The primary task of the ship, of course, is to go from A to B, but production of fresh water for the boiler to run the engine's and also for consumption by the crew was very important. But if there was a lack of fresh water it was the crew that suffered. There were no refrigerators. So the production of ice was quite important to maintain not only the beer cool, but the fresh vegetables cool. To combat this we often carried fresh meat in the form of live chickens, goats, sheep, etc. They used to live in boxes aft.

So maintaining a healthy diet was quite a task for the purser.

We had to order food at every port we arrived at. So leaving the UK, winter or summer, the first port was Port Said at the northern entrance to the Suez Canal. There we took on fresh vegetables, Egyptian new potatoes and seafood. Next stop was Aden at the bottom end of the Red Sea, where we took on further fresh produce and then that got us all the way to India. Arrival in Indian ports was quite important because we had Indian crew. So as we approached the Hooghly River, for Calcutta everybody got very excited because we knew that as we came into the river and took the river pilot, a lot of local boats would arrive with beautiful prawns, seafood, fish, papaya etc. All the fresh food we had missed on the outward voyage.

It's important to note that the ships that I sailed on had white officers, white warrant officers and Indian crew. All the food was cooked by the Indian crew. So early in the morning you would see the Bandari, the cook, squatting on the afterdeck with 2 stones 1 round and a flat 1 grinding the curry paste for the days food as we ate mainly Indian food.

For breakfast, for lunch and dinner. So although you could order an English breakfast for example, one of my favourite meals for breakfast time was kedgeree. A mixture of fish, egg and rice. Very nourishing.

Lunch time could be English food, or it could be Indian food. And the evening meal was most often a mixture of Indian and/or typical English fare. When the opportunity arose the crew and the officers would fish over the side of the ship. Whether we got fish in the Red Sea, or we got fish off Newfoundland, the crew would cook and we had fresh fish for a few days. We tried to keep a supply of fresh fish as much as possible. It was not always easy. In the Red Sea the problem was that sharks often took the fish off the hook before you got it on board. It was not unusual to land only the head of a fish. Very frustrating!

The opposite occurred off the Newfoundland coast where the sheer volume of large halibut often made it very difficult to haul the fish onboard ship.

Keeping healthy especially in tropical areas on ships without air conditioning was not easy. Once past Suez we sewed hammock for ourselves so we could sleep on deck as it was impossible to sleep in the cabins.

Weekly salt tablets and lime juice were mandatory with the scarcity of fresh vegetables and fruit.

Brocklebansk was a liner shipping company providing a scheduled service between Europe and India. As such we often carried a few passengers, and mealtime was always a social event for those not watchkeeping.

Each meal was a formal affair with silver service and waiters for all our meals. We had to dress up in our best uniforms, and the junior officers had their own table. However as a new apprentice you sat with the captain's table for a short while, but after that you're on the junior officer’s table.

When in port the meals were completely different because we kept watches, cargo watches and we used to eat breakfast at 2:00 in the morning. The port we're in often determined what sort of food we got, so in the Indian coast we got Indian food. On the American course, we've got American food.

However, some traditions were important. Christmas for example, whether we were in tropical area or whether we are in the colder climates in our blue uniforms rather than a tropical uniform we always had a English Christmas meal. That meant a bird and Christmas pudding. Plus, of course, funny hats.

The navigators toolchest- sight and sound

 Background

The Navigator possesses 2 personal traits that greatly enhance his ability to navigate. His eyes and his ears. Both require he or she have the highest medical standards for sight and hearing. Colour blindness is not an option if you are to be a deck officer as you must be able to distinguish between the major navigational colours of red, green and white.

The navigator is trained to identify conditions in his maritime environment. The sky, the horizon, sea surface and objects around him, all need to be analysed and translated into navigational decisions. He must be able to differentiate them by day or by night.

By day

During the day he normally has a focus on weather.

[1]

To start interpreting weather for navigation purposes, the navigator first turns to the barometer. The marine barometer[2] is quite special, not at all like the circular aneroid barometers seen on land. Instead it is a glass column filled with mercury. The scale on the side facilitates the reading of the top surface of the mercury. Atmospheric pressure controls the height of mercury in the tube. So a low pressure has a lower level of mercury and high pressure has a higher level.

The instrument is gimballed so the barometer stays relatively vertical during the motion of the ship.

[3]This is not the place for a technical discussion on weather systems. The navigators prime interested is how locally forecast weather will affect the ship in terms of wind, wave height and their direction. The changes in the barometer reading indicate to him the general status of local weather.

 Then he focuses on 2 prime features of the weather, the type of cloud and their height and the wind direction and its current tendency. With that information, he can make decisions to reduce bad weather affecting the ship.

This is very important when a winter storm or hurricane is near.

[4]The water surface by day also provides numerous navigational types of information. The swell and local waves help the navigator assess any danger to the ship's motion. Excessive rolling or pitching that can be a safety issue.

Changes in wind direction and strength help the navigator decide the most likely course to take.

By night

[5]The nighttime sky is a wonderful source of navigation items, the stars and the planets. They can be used to fix the ships position and give him also a relative course to steer by. First, he must identify these celestial bodies. The planets Saturn and Mars are easily identified in the northern hemisphere. Then there is the moon. The first star he searches for in the northern hemisphere is probably the Pole star.

Not very bright, but on a clear night observable. Its importance is that its altitude is also the ships latitude. A navigator can identify a range of stars useful for celestial navigation.

 The sea surface

[6]The presence of ships or land and navigational symbols are constantly monitored by the navigator. The horizon is a special case. It is where he first sees the approach of other vessels and land. At night, the loom

of the lighthouse often appears long before the light itself. Constantly sweeping horizon is a fundamental requirement of the watchkeeper.

Convention on the International Regulation for Prevention of Collisions at Sea (1972)

In addition to interpreting the natural marine environment, the navigator must be able to identify and interpret the actions of other users of the Maritime Highway.

The rules for this are embedded in the regulation for the prevention of collision at sea, colloquially called the “COLREGS”[7] He is trained to know each of the forty-one international navigational rules for conduct of vessels at sea. In addition, he must be able to identify each vessel on the sea and determine its actions. Is it a fishing boat, a ship not moving, is it anchored?

Vessels display symbols by day and lights at night to indicate their status. For example, the ship at anchor displays a black ball in the bow by day and a single white light in the same position by night.

The common set of light for all vessels are their steaming lights. They are white masthead lights, red port and green starboard lights and a white stern light. In addition there can be other lights and symbols denoting their current status.

Sound at sea

The navigator has a further sense he can use to effectively navigate. His hearing. A deck officer must have good hearing. Discerning sounds internally to the ship and externally and interpreting them is an essential safety element in navigation.

Externally, it can be one of many sound signals used to inform on the COLREGS. From changing direction, to abandoning ship or to announce your presence in reduced visibility, the ships whistle, or horn is an essential navigational tool. For example, three short blasts on the ships horn indicates the ships is running its engines astern.

Other ships announce their presence or their intentions with their horns or whistles. Light houses and buoys signify their presence in reduced visibility conditions with foghorns or bells.

All this helps the navigator fixes the ships position.

Internally the watchkeeper must be able to respond immediately to a range of sound alarms whether it be an equipment failure, presence of fire or flooding etc.

There is another sense important to the navigator and that is his sense of balance. A change in the motion the ship is instantly felt. Was it an intended action or is this something the navigator needs to address? It could be a change of course, the shifting wind or wave direction that is felt. Sometimes it is a combination of all these senses that alert the navigator to the changed status of the ship It could be changes in  engine noise or vibration or alteration of course that alerts the navigator to a change in the ships status.

The navigator must be constantly alert using all his senses.

References

‘123Capture.JPG (305×305)’. n.d. Accessed 31 August 2025. https://britastro.org/wp-content/uploads/2018/08/123Capture.JPG.

‘Don’t-Confuse-the-‘Loom’-of-the-Light-with-Its-“Dipping-Distance”.Jpg (800×377)’. n.d. Accessed 31 August 2025. https://keyassets.timeincuk.net/inspirewp/live/wp-content/uploads/sites/19/2015/08/Don%E2%80%99t-confuse-the-%E2%80%98loom%E2%80%99-of-the-light-with-its-%E2%80%98dipping-distance%E2%80%99.jpg.

in, You are not logged in-Log. ‘Kvikksølvbarometer’. Accessed 31 August 2025. https://digitaltmuseum.no/011024193297/kvikksolvbarometer.

‘Low Pressure Clouds - Google Search’. Accessed 31 August 2025. https://www.google.com/search?sca_esv=788002144cbb21b9&sxsrf=AE3TifN56Og6MJOGBUqjvHFQAA49VK-GbQ:1756647986743&udm=2&fbs=AIIjpHxU7SXXniUZfeShr2fp4giZ1Y6MJ25_tmWITc7uy4KIeqDdErwP5rACeJAty2zADJjYuUnSkczEhozYdaq1wZrEIDTyhM-aSQUsrB-ed3geL88JFzloJ36yIlLvNFOvrd4yvVOUa-6l0eI7rWgBT54Ag8yyO_tE6L9K_1dLOwaFTlEoj3BElHlxog-MP3Nt77kS6XXt&q=low+pressure+clouds&sa=X&ved=2ahUKEwjv8frZl7WPAxWLPhAIHY9wHVMQtKgLegQIExAB&biw=1136&bih=480&dpr=1.1#vhid=V-GEuVWkTcnKNM&vssid=mosaic.

‘Mariner’s Guide to Ocean Waves’. Weather Wisdom. Ocean Weather Services, 29 October 2015. https://oceanweatherservices.com/blog/2015/10/29/mariners-guide-to-ocean-waves/.

Organization, International Maritime. COLREG: Convention on the International Regulations for Preventing Collisions at Sea, 1972. IMO e-Publications, 2003. https://doi.org/10.62454/KB904E.

 

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[1] in, ‘Kvikksølvbarometer’.

[2] in, ‘Kvikksølvbarometer’.

[3] ‘Low Pressure Clouds - Google Search’.

[4] ‘Mariner’s Guide to Ocean Waves’.

[5] ‘123Capture.JPG (305×305)’.

[6] ‘Don’t-Confuse-the-‘Loom’-of-the-Light-with-Its-“Dipping-Distance”.Jpg (800×377)’.

[7] Organization, COLREG.