TECHNIQUE How to orient yourself at sea using only your hands and a watch


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Elio Somaschini
is, as of today, leading the second phase of the Velista of the Year (by the way, haven’t you voted yet?): he took a flood of votes, over 7000. So many come from Brazil, where the Lombard sailor (he was born in Seregno in 1949) moved as a boy and became famous after sailing around the world without instruments. But how did he do it? In this article we had summarized it for you, now he himself tells us about it in a very detailed article. And useful should you be in total “blackout” and the tools are not working. Read and … practice!(illustration by Luna Poggi)


In this article I would like to talk about a great Pacific Ocean sailor and how he changed my life and the way I sail.


One of history’s great navigators, though little known in the West, is Pius “Mau” Piailug. Mau is not his name, but a nickname meaning “strong,” due to the fact that he spent hours and days at sea; members of his village said that was why he was strong. In the’50s, when he was in his early twenties, he received the title of Pwoin: a solemn ceremony, as the last descendant who still retained the knowledge that enabled the man to integrate with nature, undertake sea voyages and protect the village.

Pius “Mau” Piailug

Until the 1960s, it was believed that American Indians were descendants of Asian peoples who would cross the Bering Strait, taking advantage of periods of frost, and then descend along the continent and populate it. However, a group at the University of Hawaii thought differently: they thought that the Native Americans were descendants of Pacific Islander ethnic groups and that these were not populated fortuitously.

To prove that this could be true, they would first have to prove that such peoples were capable of navigating between their islands and,from there, to our continent. Some patrons accepted the challenge, and as many archaeologists succeeded in reconstructing a canoe with the ancient features of the time. The problem was where to find someone capable of navigating that strange “thing” and, moreover, making long trips using techniques and resources from about a thousand years ago.

Thus,the search for the supposed navigator began; everyone pointed to Mau Piailug as the only one capable of such a feat. They went to the island where he lived in Micronesia and invited him to participate in the project. He accepted.He was about 36 years old at the time. They put Mau on a plane (he had never flown!) and took him to Hawaii. But he had no idea where he was. When they showed him the boat, Mau gave a big smile, saying that it was similar to his grandfather’s, but had some mistakes. These were immediately corrected under his supervision.

They asked him if he was able to sail to Tahiti in that boat, and he replied, “I don’t know where I am; if you leave me for a week on a beach away from the lights to study the sky and sea, I will tell you if I can make it.” A week later, he said, “I know where I am,I know where Tahiti is because my ancestors told me about it and, therefore, I have a clear idea of where it is, so I know how to get there!”

He would have to start the journey from a place he had never been before to get to a place he knew existed, thanks to stories told by his grandfather, but where he had never been, on a boat without any tools, trusting only his ability to integrate with nature! This trip was historic. He traveled more than 2,300 miles without any instruments, guided by the sun, stars, waves, and using his hands to measure angles!

A beautiful film was made about this memorable journey, PapaMau: The Wayfinder. An excellent account, with exact information about the life and works of Pius Mau Piailug, can be found here.


I never met Mau Piailug, but I did meet one of his disciples who taught me a lot. One evening, on the sand on the beach in front of his home on the atoll where he lives with his wife, Pow Maori, that’s his name, told me,“Every island has its star.”

This has stuck in my mind. I finally got it! Stars apparently revolve around the Earth, and the intersection of the line joining them with the center of the Earth and the Earth’s surface (the sea) always forms a parallel. Thus, for every island there is at least one bright star that passes over the island every day (or every night)! Mind you, this does not apply to the Sun, Moon or planets, only to stars.

Before starting a navigation, Mau would build a compass out of shells in the sand. He divided the circle into 4 quadrants and later divided each quadrant two more times. At night he would look for the passing star on the island he wanted to reach and mark the spot where he was born and where he died. In this way, he knew the direction he needed to go (i.e., he knew the parallel where the island was!).

In the compass in the photo, it is also understood that the 8 directions from where a“swell” can come, the “swells” that arrive as an outcome of a pertubation (in that region of the Pacific) are marked, and pushing the shell further outward means increasing the size of that swell.

All of this was done (and still is done) by measuring angles with your hands(WE HAVE TOLD YOU ABOUT IT HERE).
Upon reaching the parallel, it continued east or west-as the case may be-until it reached the island.

It is clear that all this has a certain margin of error; in truth he imagined a square around the island and when he thought he was close to it, that is, within the square, he looked for other signs such as birds, clouds, waves, etc., that might have shown him the exact location.

Just like the ancient great explorers, he would navigate using latitude and later follow the parallel until he reached the destination. As with other ancient navigators, however, they lacked longitude.

This is why ancient maps were good vertically (latitude), but incredibly disproportionate horizontally (longitude).
The knowledge of longitude was lacking. When I learned this technique, I knew right away that we could add something to it. We have the clock, and with that we can know the longitude.

The clock marks 24 hours of a day, which is the average solar day, but the stars turn faster than the Sun: they make a full circle in just over 23 hours and 56 minutes (sidereal day).

So,if at night you always look at the sky at the same time, you will see that every day the stars appear 4 minutes earlier than the day before and you will notice that, with almost four minutes a day multiplied by 360 days a year, they make a complete circle; that is, every day, at the same time,the stars advance 1 degree! This, too, was already well known more than two thousand years ago. The Phoenicians and the Egyptians already knew this!

We navigators use the mile as a measure of distance, and this has reason to be. If you take the Earth’s maximum circle and measure the arc of a minute, its length will be one mile. Since one degree has 60 minutes, one degree is equivalent to 60 nautical miles. You must have studied this in the skipper’s course, and it is a more than well-known fact.

So what is the method I developed using these known facts?


Initially I look for the coordinates of the location of where I am. For example: Paraty, Lat.-23.21 and Long.44.71 W, so I evaluate the coordinates of where I want to go, for example Trindade and Martin Vaz (Lat.-20.52e Long. 29.32 W).

Assuming that I will have to sail eastward about 15 degrees, in the direction of Sunrise, this should represent 900 miles. However, the parallel passing through Paraty is not a maximum circle, so I have to use the cosine of the latitude as a correction factor. Multiplying 900 by 0.95 (which is the cosine of 20 degrees), I should sail about 850 miles eastward, and 180 miles northward.

The night before the start of the journey I draw on a sheet of paper the stars (especially those that are rising and those that are dying) at a certain time, for example at midnight. I know, therefore, what the sky looks like at the starting point and at that particular time.
After 4 days of sailing eastward, before midnight, I observe the sky with a paper in my hand. If, for example, the sky is the same as my drawing at 11 p.m. and 12 minutes, I know that:

A) If I had not moved and was still in Paraty, the stars would look like this at 11:44 p.m. (4 minutes x 4 days = 16 minutes. Midnight minus 16 minutes = 11:44 p.m.).

B) Since I see this at 11:12 p.m., it means that I have been sailing in the direction of starrise (East) for 32 minutes (11:44 p.m. minus 11:12 p.m.).

C) Since 4 minutes corresponds to 1 degree, or 60 miles x cos20, I sailed 8x60x0.95 = 456 miles, heading east.

I know, therefore, my longitude in relation to Paraty!

There still remains the easy problem of latitude, but this is measured using the Southern Cross in the Southern Hemisphere, or the North Star in the Northern Hemisphere. So I know my latitude and longitude with good accuracy! I know where they are!

Interestingly, in the example I used, the line of the parallel passing through Paraty, the intersection of the Martin Vaz meridian and the line joining Paraty to Martin Vaz practically form an isosceles triangle, so if I can sail directly to Martin Vaz,I will have to travel a little over 850 miles in the whole trip.

The fact that I use my hands is not important; you can use an astrolabe or a protractor with a string and a screw and it will work perfectly.

With this you can navigate your way around the world. You just have to be alert to the fact that the error will be greater the farther you are from the Equator. This system works very well in the tropics, outside of them you have to practice well and there are techniques for observing the stars.

My method has nothing new, I just grouped the knowledge of Pacific peoples with the use of the clock and simple notions of astronomy.


But Pow’s knowledge goes far beyond simply indicating the position of the sun and stars. Sea waves are a great source of information. Mau Piailug could identify where storms had formed, for how long, what their strength was. He was also able to identify up to five types of waves that crossed in the ocean where he sailed.

I was able to identify a combination of three while sailing in the Mediterranean towards Lampedusa. I realized that there must have been bad weather in the Adriatic.
When I arrived in Lampedusa, I phoned a friend who lives in Trieste and he confirmed that five days earlier the Bora had swept through the city. It made me very happy to realize that, with much observation and exercise, we can perceive what nature has to tell us.

Elio Somaschini

If you are sailing in front of a coastline with rocks sloping over the sea, you will clearly perceive two different directions (at a minimum) of wave propagation. Try to observe them, it is easy, they are well defined. One is from the ocean and the other is from land, a reflection of those incidents on local rocks. Just look for what nature has to tell us.

Elio Somaschini “Crapun”



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